21355474 has 24 divisors (see below), whose sum is σ = 37428480. Its totient is φ = 9111816.

The previous prime is 21355471. The next prime is 21355483. The reversal of 21355474 is 47455312.

It is not an unprimeable number, because it can be changed into a prime (21355471) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 34879 + ... + 35485.

It is an arithmetic number, because the mean of its divisors is an integer number (1559520).

Almost surely, 2^21355474 is an apocalyptic number.

21355474 is a deficient number, since it is larger than the sum of its proper divisors (16073006).

21355474 is a wasteful number, since it uses less digits than its factorization.

21355474 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 982 (or 975 counting only the distinct ones).

The product of its digits is 16800, while the sum is 31.

The square root of 21355474 is about 4621.1983294379. The cubic root of 21355474 is about 277.4404233221.

The spelling of 21355474 in words is "twenty-one million, three hundred fifty-five thousand, four hundred seventy-four".