21056854 has 32 divisors (see below), whose sum is σ = 39223296. Its totient is φ = 8255520.

The previous prime is 21056839. The next prime is 21056869. The reversal of 21056854 is 45865012.

It is an interprime number because it is at equal distance from previous prime (21056839) and next prime (21056869).

It is a super-2 number, since 2×21056854² = 886782200754632, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22659 + ... + 23569.

It is an arithmetic number, because the mean of its divisors is an integer number (1225728).

Almost surely, 2^21056854 is an apocalyptic number.

21056854 is a deficient number, since it is larger than the sum of its proper divisors (18166442).

21056854 is a wasteful number, since it uses less digits than its factorization.

21056854 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1060.

The product of its (nonzero) digits is 9600, while the sum is 31.

The square root of 21056854 is about 4588.7747820088. The cubic root of 21056854 is about 276.1411708666.

The spelling of 21056854 in words is "twenty-one million, fifty-six thousand, eight hundred fifty-four".