21929898 has 24 divisors (see below), whose sum is σ = 46595232. Its totient is φ = 6879424.

The previous prime is 21929893. The next prime is 21929903. The reversal of 21929898 is 89892912.

It is an interprime number because it is at equal distance from previous prime (21929893) and next prime (21929903).

It is not an unprimeable number, because it can be changed into a prime (21929893) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4590 + ... + 8057.

It is an arithmetic number, because the mean of its divisors is an integer number (1941468).

Almost surely, 2^21929898 is an apocalyptic number.

21929898 is an abundant number, since it is smaller than the sum of its proper divisors (24665334).

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

21929898 is a wasteful number, since it uses less digits than its factorization.

21929898 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12686 (or 12669 counting only the distinct ones).

The product of its digits is 186624, while the sum is 48.

The square root of 21929898 is about 4682.9368989983. The cubic root of 21929898 is about 279.9059973562.

It can be divided in two parts, 2192 and 9898, that added together give a triangular number (12090 = T₁₅₅).

The spelling of 21929898 in words is "twenty-one million, nine hundred twenty-nine thousand, eight hundred ninety-eight".