21217058 has 16 divisors (see below), whose sum is σ = 32904960. Its totient is φ = 10252656.

The previous prime is 21217039. The next prime is 21217087. The reversal of 21217058 is 85071212.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11183 + ... + 12941.

It is an arithmetic number, because the mean of its divisors is an integer number (2056560).

Almost surely, 2^21217058 is an apocalyptic number.

21217058 is a deficient number, since it is larger than the sum of its proper divisors (11687902).

21217058 is a wasteful number, since it uses less digits than its factorization.

21217058 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1961.

The product of its (nonzero) digits is 1120, while the sum is 26.

The square root of 21217058 is about 4606.1977812508. The cubic root of 21217058 is about 276.8397114247.

The spelling of 21217058 in words is "twenty-one million, two hundred seventeen thousand, fifty-eight".