21135490 has 32 divisors (see below), whose sum is σ = 40642560. Its totient is φ = 7896000.

The previous prime is 21135481. The next prime is 21135503. The reversal of 21135490 is 9453112.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7815 + ... + 10165.

It is an arithmetic number, because the mean of its divisors is an integer number (1270080).

Almost surely, 2^21135490 is an apocalyptic number.

21135490 is a deficient number, since it is larger than the sum of its proper divisors (19507070).

21135490 is a wasteful number, since it uses less digits than its factorization.

21135490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2418.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 21135490 is about 4597.3350976408. The cubic root of 21135490 is about 276.4844899941.

The spelling of 21135490 in words is "twenty-one million, one hundred thirty-five thousand, four hundred ninety".