20516975 has 6 divisors (see below), whose sum is σ = 25441080. Its totient is φ = 16413560.

The previous prime is 20516953. The next prime is 20516999. The reversal of 20516975 is 57961502.

It is not a de Polignac number, because 20516975 - 2⁶ = 20516911 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 410315 + ... + 410364.

It is an arithmetic number, because the mean of its divisors is an integer number (4240180).

Almost surely, 2^20516975 is an apocalyptic number.

20516975 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20516975 is a deficient number, since it is larger than the sum of its proper divisors (4924105).

20516975 is an equidigital number, since it uses as much as digits as its factorization.

20516975 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 820689 (or 820684 counting only the distinct ones).

The product of its (nonzero) digits is 18900, while the sum is 35.

The square root of 20516975 is about 4529.5667563245. The cubic root of 20516975 is about 273.7607044597.

The spelling of 20516975 in words is "twenty million, five hundred sixteen thousand, nine hundred seventy-five".