21690538171632 has 800 divisors, whose sum is σ = 73771787232000. Its totient is φ = 6079433564160.

The previous prime is 21690538171543. The next prime is 21690538171681. The reversal of 21690538171632 is 23617183509612.

It is a happy number.

21690538171632 is a `hidden beast` number, since 2 + 1 + 6 + 9 + 0 + 538 + 1 + 71 + 6 + 32 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 8102553078 + ... + 8102555754.

It is an arithmetic number, because the mean of its divisors is an integer number (92214734040).

Almost surely, 2^{21690538171632} is an apocalyptic number.

21690538171632 is a gapful number since it is divisible by the number (22) 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 21690538171632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36885893616000).

21690538171632 is an abundant number, since it is smaller than the sum of its proper divisors (52081249060368).

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

21690538171632 is a wasteful number, since it uses less digits than its factorization.

21690538171632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3291 (or 3276 counting only the distinct ones).

The product of its (nonzero) digits is 3265920, while the sum is 54.

The spelling of 21690538171632 in words is "twenty-one trillion, six hundred ninety billion, five hundred thirty-eight million, one hundred seventy-one thousand, six hundred thirty-two".