921200916636 has 576 divisors, whose sum is σ = 3254787916800. Its totient is φ = 219239032320.

The previous prime is 921200916593. The next prime is 921200916667. The reversal of 921200916636 is 636619002129.

921200916636 is a `hidden beast` number, since 9 + 2 + 1 + 2 + 0 + 0 + 9 + 1 + 6 + 636 = 666.

It is a super-2 number, since 2×921200916636² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 921200916591 and 921200916600.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 165294346 + ... + 165299918.

Almost surely, 2^921200916636 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 921200916636, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1627393958400).

921200916636 is an abundant number, since it is smaller than the sum of its proper divisors (2333587000164).

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

921200916636 is a wasteful number, since it uses less digits than its factorization.

921200916636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5767 (or 5748 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 45.

The spelling of 921200916636 in words is "nine hundred twenty-one billion, two hundred million, nine hundred sixteen thousand, six hundred thirty-six".