221172140 has 48 divisors (see below), whose sum is σ = 553900032. Its totient is φ = 72532416.

The previous prime is 221172131. The next prime is 221172143. The reversal of 221172140 is 41271122.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (221172143) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31124 + ... + 37563.

It is an arithmetic number, because the mean of its divisors is an integer number (11539584).

Almost surely, 2^221172140 is an apocalyptic number.

221172140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221172140 is an abundant number, since it is smaller than the sum of its proper divisors (332727892).

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

221172140 is a wasteful number, since it uses less digits than its factorization.

221172140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68726 (or 68724 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 20.

The square root of 221172140 is about 14871.8573150767. The cubic root of 221172140 is about 604.7512945378.

The spelling of 221172140 in words is "two hundred twenty-one million, one hundred seventy-two thousand, one hundred forty".