21992670 has 72 divisors (see below), whose sum is σ = 66529944. Its totient is φ = 5025888.

The previous prime is 21992657. The next prime is 21992693. The reversal of 21992670 is 7629912.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1917 + ... + 6903.

It is an arithmetic number, because the mean of its divisors is an integer number (924027).

Almost surely, 2^21992670 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21992670, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33264972).

21992670 is an abundant number, since it is smaller than the sum of its proper divisors (44537274).

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

21992670 is a wasteful number, since it uses less digits than its factorization.

21992670 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5014 (or 5004 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 36.

The square root of 21992670 is about 4689.6343141017. The cubic root of 21992670 is about 280.1728099901.

The spelling of 21992670 in words is "twenty-one million, nine hundred ninety-two thousand, six hundred seventy".