20309968 has 40 divisors (see below), whose sum is σ = 47621952. Its totient is φ = 8191488.

The previous prime is 20309959. The next prime is 20309999. The reversal of 20309968 is 86990302.

It is a super-2 number, since 2×20309968² = 824989600322048, which contains 22 as substring.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3430 + ... + 7237.

Almost surely, 2^20309968 is an apocalyptic number.

20309968 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

20309968 is an abundant number, since it is smaller than the sum of its proper divisors (27311984).

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

20309968 is a wasteful number, since it uses less digits than its factorization.

20309968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10699 (or 10693 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 37.

The square root of 20309968 is about 4506.6581853964. The cubic root of 20309968 is about 272.8368832407.

The spelling of 20309968 in words is "twenty million, three hundred nine thousand, nine hundred sixty-eight".