61771604400 has 600 divisors, whose sum is σ = 249693447168. Its totient is φ = 14489280000.

The previous prime is 61771604399. The next prime is 61771604429. The reversal of 61771604400 is 440617716.

61771604400 is a `hidden beast` number, since 6 + 1 + 7 + 7 + 1 + 604 + 40 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (600).

It is a super-2 number, since 2×61771604400² (a number of 22 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

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

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 11045605 + ... + 11051195.

Almost surely, 2^61771604400 is an apocalyptic number.

61771604400 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61771604400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124846723584).

61771604400 is an abundant number, since it is smaller than the sum of its proper divisors (187921842768).

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

61771604400 is a wasteful number, since it uses less digits than its factorization.

61771604400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5663 (or 5643 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 36.

The spelling of 61771604400 in words is "sixty-one billion, seven hundred seventy-one million, six hundred four thousand, four hundred".