221671472400 has 1215 divisors, whose sum is σ = 960710413221. Its totient is φ = 47187463680.

The previous prime is 221671472359. The next prime is 221671472401. The reversal of 221671472400 is 4274176122.

The square root of 221671472400 is 470820.

It is a perfect power (a square), and thus also a powerful number.

221671472400 is a `hidden beast` number, since 22 + 167 + 1 + 4 + 72 + 400 = 666.

It can be written as a sum of positive squares in only one way, i.e., 79801730064 + 141869742336 = 282492^2 + 376656^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (221671472401) by changing a digit.

It is a polite number, since it can be written in 242 ways as a sum of consecutive naturals, for example, 3757143571 + ... + 3757143629.

Almost surely, 2^221671472400 is an apocalyptic number.

221671472400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

221671472400 is the 470820-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221671472400

221671472400 is an abundant number, since it is smaller than the sum of its proper divisors (739038940821).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221671472400 is a wasteful number, since it uses less digits than its factorization.

221671472400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 194 (or 95 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 36.

Multiplying 221671472400 by its sum of digits (36), we get a square (7980173006400 = 2824920²).

221671472400 divided by its sum of digits (36) gives a square (6157540900 = 78470²).

The spelling of 221671472400 in words is "two hundred twenty-one billion, six hundred seventy-one million, four hundred seventy-two thousand, four hundred".