20515995 has 24 divisors (see below), whose sum is σ = 35792016. Its totient is φ = 10870848.

The previous prime is 20515967. The next prime is 20516009. The reversal of 20515995 is 59951502.

It is not a de Polignac number, because 20515995 - 2⁸ = 20515739 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5937 + ... + 8733.

It is an arithmetic number, because the mean of its divisors is an integer number (1491334).

Almost surely, 2^20515995 is an apocalyptic number.

20515995 is a deficient number, since it is larger than the sum of its proper divisors (15276021).

20515995 is a wasteful number, since it uses less digits than its factorization.

20515995 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2971 (or 2968 counting only the distinct ones).

The product of its (nonzero) digits is 20250, while the sum is 36.

The square root of 20515995 is about 4529.4585769162. The cubic root of 20515995 is about 273.7563456339.

The spelling of 20515995 in words is "twenty million, five hundred fifteen thousand, nine hundred ninety-five".