21371490 has 48 divisors (see below), whose sum is σ = 63505728. Its totient is φ = 4884768.

The previous prime is 21371489. The next prime is 21371509. The reversal of 21371490 is 9417312.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16332 + ... + 17591.

It is an arithmetic number, because the mean of its divisors is an integer number (1323036).

Almost surely, 2^21371490 is an apocalyptic number.

21371490 is an abundant number, since it is smaller than the sum of its proper divisors (42134238).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21371490 is a wasteful number, since it uses less digits than its factorization.

21371490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33943 (or 33940 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 21371490 is about 4622.9308885165. The cubic root of 21371490 is about 277.5097634744.

The spelling of 21371490 in words is "twenty-one million, three hundred seventy-one thousand, four hundred ninety".