21510068 has 12 divisors (see below), whose sum is σ = 37679040. Its totient is φ = 10744632.

The previous prime is 21510053. The next prime is 21510077. The reversal of 21510068 is 86001512.

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, 3803 + ... + 7581.

It is an arithmetic number, because the mean of its divisors is an integer number (3139920).

Almost surely, 2^21510068 is an apocalyptic number.

It is an amenable number.

21510068 is a deficient number, since it is larger than the sum of its proper divisors (16168972).

21510068 is a wasteful number, since it uses less digits than its factorization.

21510068 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5206 (or 5204 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 23.

The square root of 21510068 is about 4637.8947810402. The cubic root of 21510068 is about 278.1082855418.

The spelling of 21510068 in words is "twenty-one million, five hundred ten thousand, sixty-eight".