21142992 has 80 divisors (see below), whose sum is σ = 60773888. Its totient is φ = 6289920.

The previous prime is 21142981. The next prime is 21143009. The reversal of 21142992 is 29924112.

It is a happy number.

It is a super-2 number, since 2×21142992² = 894052221424128, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18798 + ... + 19890.

Almost surely, 2^21142992 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21142992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30386944).

21142992 is an abundant number, since it is smaller than the sum of its proper divisors (39630896).

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

21142992 is a wasteful number, since it uses less digits than its factorization.

21142992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1148 (or 1142 counting only the distinct ones).

The product of its digits is 2592, while the sum is 30.

The square root of 21142992 is about 4598.1509327120. The cubic root of 21142992 is about 276.5171986638.

The spelling of 21142992 in words is "twenty-one million, one hundred forty-two thousand, nine hundred ninety-two".