21554924 has 12 divisors (see below), whose sum is σ = 37824864. Its totient is φ = 10747824.

The previous prime is 21554921. The next prime is 21554927. The reversal of 21554924 is 42945512.

It is an interprime number because it is at equal distance from previous prime (21554921) and next prime (21554927).

It is a super-2 number, since 2×21554924² = 929229497291552, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21554921) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 5732 + ... + 8715.

It is an arithmetic number, because the mean of its divisors is an integer number (3152072).

Almost surely, 2^21554924 is an apocalyptic number.

It is an amenable number.

21554924 is a deficient number, since it is larger than the sum of its proper divisors (16269940).

21554924 is a wasteful number, since it uses less digits than its factorization.

21554924 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14824 (or 14822 counting only the distinct ones).

The product of its digits is 14400, while the sum is 32.

The square root of 21554924 is about 4642.7280773270. The cubic root of 21554924 is about 278.3014689360.

The spelling of 21554924 in words is "twenty-one million, five hundred fifty-four thousand, nine hundred twenty-four".