21368708 has 24 divisors (see below), whose sum is σ = 39637080. Its totient is φ = 10062080.

The previous prime is 21368707. The next prime is 21368713. The reversal of 21368708 is 80786312.

It can be written as a sum of positive squares in 4 ways, for example, as 4656964 + 16711744 = 2158^2 + 4088^2 .

It is not an unprimeable number, because it can be changed into a prime (21368707) 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, 2510 + ... + 7002.

It is an arithmetic number, because the mean of its divisors is an integer number (1651545).

Almost surely, 2^21368708 is an apocalyptic number.

It is an amenable number.

21368708 is a deficient number, since it is larger than the sum of its proper divisors (18268372).

21368708 is a wasteful number, since it uses less digits than its factorization.

21368708 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4567 (or 4565 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 21368708 is about 4622.6299873557. The cubic root of 21368708 is about 277.4977214866.

It can be divided in two parts, 213 and 68708, that added together give a cube (68921 = 41³).

The spelling of 21368708 in words is "twenty-one million, three hundred sixty-eight thousand, seven hundred eight".