21192690 has 32 divisors (see below), whose sum is σ = 51057216. Its totient is φ = 5629760.

The previous prime is 21192671. The next prime is 21192709. The reversal of 21192690 is 9629112.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21192671) and next prime (21192709).

It is a super-2 number, since 2×21192690² = 898260218872200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7585 + ... + 9995.

It is an arithmetic number, because the mean of its divisors is an integer number (1595538).

Almost surely, 2^21192690 is an apocalyptic number.

21192690 is an abundant number, since it is smaller than the sum of its proper divisors (29864526).

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

21192690 is a wasteful number, since it uses less digits than its factorization.

21192690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2714.

The product of its (nonzero) digits is 1944, while the sum is 30.

The square root of 21192690 is about 4603.5518895740. The cubic root of 21192690 is about 276.7336864460.

The spelling of 21192690 in words is "twenty-one million, one hundred ninety-two thousand, six hundred ninety".