21898756 has 48 divisors (see below), whose sum is σ = 43747200. Its totient is φ = 9504000.

The previous prime is 21898753. The next prime is 21898763. The reversal of 21898756 is 65789812.

It is not an unprimeable number, because it can be changed into a prime (21898753) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 109945 + ... + 110143.

It is an arithmetic number, because the mean of its divisors is an integer number (911400).

Almost surely, 2^21898756 is an apocalyptic number.

It is an amenable number.

21898756 is a deficient number, since it is larger than the sum of its proper divisors (21848444).

21898756 is a wasteful number, since it uses less digits than its factorization.

21898756 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316 (or 314 counting only the distinct ones).

The product of its digits is 241920, while the sum is 46.

The square root of 21898756 is about 4679.6106675663. The cubic root of 21898756 is about 279.7734391777.

It can be divided in two parts, 2189 and 8756, that multiplied together give a square (19166884 = 4378²).

The spelling of 21898756 in words is "twenty-one million, eight hundred ninety-eight thousand, seven hundred fifty-six".