921707838 has 24 divisors (see below), whose sum is σ = 2043478008. Its totient is φ = 300090672.

The previous prime is 921707827. The next prime is 921707867. The reversal of 921707838 is 838707129.

It is a junction number, because it is equal to n+sod(n) for n = 921707793 and 921707802.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 594645 + ... + 596192.

It is an arithmetic number, because the mean of its divisors is an integer number (85144917).

Almost surely, 2^921707838 is an apocalyptic number.

921707838 is an abundant number, since it is smaller than the sum of its proper divisors (1121770170).

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

921707838 is a wasteful number, since it uses less digits than its factorization.

921707838 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1190888 (or 1190885 counting only the distinct ones).

The product of its (nonzero) digits is 169344, while the sum is 45.

The square root of 921707838 is about 30359.6415986750. The cubic root of 921707838 is about 973.1902745532.

The spelling of 921707838 in words is "nine hundred twenty-one million, seven hundred seven thousand, eight hundred thirty-eight".