20916951 has 24 divisors (see below), whose sum is σ = 31336704. Its totient is φ = 12307680.

The previous prime is 20916949. The next prime is 20916979. The reversal of 20916951 is 15961902.

It is not a de Polignac number, because 20916951 - 2¹ = 20916949 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20916941) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 44946 + ... + 45408.

It is an arithmetic number, because the mean of its divisors is an integer number (1305696).

Almost surely, 2^20916951 is an apocalyptic number.

20916951 is a deficient number, since it is larger than the sum of its proper divisors (10419753).

20916951 is a wasteful number, since it uses less digits than its factorization.

20916951 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 551 (or 514 counting only the distinct ones).

The product of its (nonzero) digits is 4860, while the sum is 33.

The square root of 20916951 is about 4573.5053296132. The cubic root of 20916951 is about 275.5282452544.

The spelling of 20916951 in words is "twenty million, nine hundred sixteen thousand, nine hundred fifty-one".