21602138 has 16 divisors (see below), whose sum is σ = 34426944. Its totient is φ = 10130880.

The previous prime is 21602137. The next prime is 21602143. The reversal of 21602138 is 83120612.

It is not an unprimeable number, because it can be changed into a prime (21602137) 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, 10883 + ... + 12713.

It is an arithmetic number, because the mean of its divisors is an integer number (2151684).

Almost surely, 2^21602138 is an apocalyptic number.

21602138 is a deficient number, since it is larger than the sum of its proper divisors (12824806).

21602138 is a wasteful number, since it uses less digits than its factorization.

21602138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2197.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 21602138 is about 4647.8100219351. The cubic root of 21602138 is about 278.5045183404.

The spelling of 21602138 in words is "twenty-one million, six hundred two thousand, one hundred thirty-eight".