21121792 has 18 divisors (see below), whose sum is σ = 42161588. Its totient is φ = 10560768.

The previous prime is 21121781. The next prime is 21121811. The reversal of 21121792 is 29712112.

It is a super-2 number, since 2×21121792² = 892260194582528, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40998 + ... + 41509.

Almost surely, 2^21121792 is an apocalyptic number.

It is an amenable number.

21121792 is a deficient number, since it is larger than the sum of its proper divisors (21039796).

21121792 is an frugal number, since it uses more digits than its factorization.

21121792 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82523 (or 82509 counting only the distinct ones).

The product of its digits is 504, while the sum is 25.

The square root of 21121792 is about 4595.8450800696. The cubic root of 21121792 is about 276.4247468319.

The spelling of 21121792 in words is "twenty-one million, one hundred twenty-one thousand, seven hundred ninety-two".