688922421 has 32 divisors (see below), whose sum is σ = 1016873088. Its totient is φ = 411402240.

The previous prime is 688922419. The next prime is 688922431. The reversal of 688922421 is 124229886.

It is not a de Polignac number, because 688922421 - 2¹ = 688922419 is a prime.

It is a super-2 number, since 2×688922421² = 949228204313002482, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688922431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1193685 + ... + 1194261.

It is an arithmetic number, because the mean of its divisors is an integer number (31777284).

Almost surely, 2^688922421 is an apocalyptic number.

It is an amenable number.

688922421 is a deficient number, since it is larger than the sum of its proper divisors (327950667).

688922421 is a wasteful number, since it uses less digits than its factorization.

688922421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1061.

The product of its digits is 110592, while the sum is 42.

The square root of 688922421 is about 26247.3316929550. The cubic root of 688922421 is about 883.1953483607.

The spelling of 688922421 in words is "six hundred eighty-eight million, nine hundred twenty-two thousand, four hundred twenty-one".