21608402 has 8 divisors (see below), whose sum is σ = 32627712. Its totient is φ = 10732500.

The previous prime is 21608387. The next prime is 21608417. The reversal of 21608402 is 20480612.

It is an interprime number because it is at equal distance from previous prime (21608387) and next prime (21608417).

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

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, 35474 + ... + 36077.

It is an arithmetic number, because the mean of its divisors is an integer number (4078464).

Almost surely, 2^21608402 is an apocalyptic number.

21608402 is a deficient number, since it is larger than the sum of its proper divisors (11019310).

21608402 is a wasteful number, since it uses less digits than its factorization.

21608402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71704.

The product of its (nonzero) digits is 768, while the sum is 23.

The square root of 21608402 is about 4648.4838388447. The cubic root of 21608402 is about 278.5314351778.

The spelling of 21608402 in words is "twenty-one million, six hundred eight thousand, four hundred two".