20931716 has 24 divisors (see below), whose sum is σ = 39588864. Its totient is φ = 9626400.

The previous prime is 20931683. The next prime is 20931719. The reversal of 20931716 is 61713902.

It is a Smith number, since the sum of its digits (29) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (20931719) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19391 + ... + 20441.

It is an arithmetic number, because the mean of its divisors is an integer number (1649536).

Almost surely, 2^20931716 is an apocalyptic number.

20931716 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

20931716 is a deficient number, since it is larger than the sum of its proper divisors (18657148).

20931716 is a wasteful number, since it uses less digits than its factorization.

20931716 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1451 (or 1449 counting only the distinct ones).

The product of its (nonzero) digits is 2268, while the sum is 29.

The square root of 20931716 is about 4575.1192334189. The cubic root of 20931716 is about 275.5930605915.

The spelling of 20931716 in words is "twenty million, nine hundred thirty-one thousand, seven hundred sixteen".