20976505 has 16 divisors (see below), whose sum is σ = 27720000. Its totient is φ = 15111360.

The previous prime is 20976479. The next prime is 20976509. The reversal of 20976505 is 50567902.

It is not a de Polignac number, because 20976505 - 2⁷ = 20976377 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20976509) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4246 + ... + 7744.

It is an arithmetic number, because the mean of its divisors is an integer number (1732500).

Almost surely, 2^20976505 is an apocalyptic number.

It is an amenable number.

20976505 is a deficient number, since it is larger than the sum of its proper divisors (6743495).

20976505 is a wasteful number, since it uses less digits than its factorization.

20976505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3624.

The product of its (nonzero) digits is 18900, while the sum is 34.

The square root of 20976505 is about 4580.0114628678. The cubic root of 20976505 is about 275.7894888879.

The spelling of 20976505 in words is "twenty million, nine hundred seventy-six thousand, five hundred five".