21616474 has 16 divisors (see below), whose sum is σ = 36041760. Its totient is φ = 9639760.

The previous prime is 21616459. The next prime is 21616477. The reversal of 21616474 is 47461612.

It is not an unprimeable number, because it can be changed into a prime (21616477) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8104 + ... + 10435.

It is an arithmetic number, because the mean of its divisors is an integer number (2252610).

Almost surely, 2^21616474 is an apocalyptic number.

21616474 is a deficient number, since it is larger than the sum of its proper divisors (14425286).

21616474 is a wasteful number, since it uses less digits than its factorization.

21616474 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18605.

The product of its digits is 8064, while the sum is 31.

The square root of 21616474 is about 4649.3519978595. The cubic root of 21616474 is about 278.5661134454.

The spelling of 21616474 in words is "twenty-one million, six hundred sixteen thousand, four hundred seventy-four".