21139492 has 24 divisors (see below), whose sum is σ = 41751360. Its totient is φ = 9276960.

The previous prime is 21139453. The next prime is 21139513. The reversal of 21139492 is 29493112.

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 in 7 ways as a sum of consecutive naturals, for example, 7008 + ... + 9559.

It is an arithmetic number, because the mean of its divisors is an integer number (1739640).

Almost surely, 2^21139492 is an apocalyptic number.

21139492 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21139492 is a deficient number, since it is larger than the sum of its proper divisors (20611868).

21139492 is a wasteful number, since it uses less digits than its factorization.

21139492 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16611 (or 16609 counting only the distinct ones).

The product of its digits is 3888, while the sum is 31.

The square root of 21139492 is about 4597.7703291922. The cubic root of 21139492 is about 276.5019396503.

The spelling of 21139492 in words is "twenty-one million, one hundred thirty-nine thousand, four hundred ninety-two".