21142608 has 20 divisors (see below), whose sum is σ = 54618528. Its totient is φ = 7047520.

The previous prime is 21142531. The next prime is 21142613. The reversal of 21142608 is 80624112.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

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, 220188 + ... + 220283.

Almost surely, 2^21142608 is an apocalyptic number.

It is an amenable number.

21142608 is an abundant number, since it is smaller than the sum of its proper divisors (33475920).

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

21142608 is a wasteful number, since it uses less digits than its factorization.

21142608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 440482 (or 440476 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 24.

The square root of 21142608 is about 4598.1091766073. The cubic root of 21142608 is about 276.5155246143.

The spelling of 21142608 in words is "twenty-one million, one hundred forty-two thousand, six hundred eight".