21480538 has 8 divisors (see below), whose sum is σ = 32274720. Its totient is φ = 10722300.

The previous prime is 21480499. The next prime is 21480541. The reversal of 21480538 is 83508412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21480538² = 922827025538888, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7438 + ... + 9913.

It is an arithmetic number, because the mean of its divisors is an integer number (4034340).

Almost surely, 2^21480538 is an apocalyptic number.

21480538 is a deficient number, since it is larger than the sum of its proper divisors (10794182).

21480538 is a wasteful number, since it uses less digits than its factorization.

21480538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17972.

The product of its (nonzero) digits is 7680, while the sum is 31.

The square root of 21480538 is about 4634.7101311733. The cubic root of 21480538 is about 277.9809606891.

The spelling of 21480538 in words is "twenty-one million, four hundred eighty thousand, five hundred thirty-eight".