21111792 has 80 divisors (see below), whose sum is σ = 61329408. Its totient is φ = 6209280.

The previous prime is 21111791. The next prime is 21111821. The reversal of 21111792 is 29711112.

It is a super-2 number, since 2×21111792² = 891415522902528, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21111791) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13617 + ... + 15087.

Almost surely, 2^21111792 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 21111792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30664704).

21111792 is an abundant number, since it is smaller than the sum of its proper divisors (40217616).

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

21111792 is a wasteful number, since it uses less digits than its factorization.

21111792 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1518 (or 1512 counting only the distinct ones).

The product of its digits is 252, while the sum is 24.

The square root of 21111792 is about 4594.7570120737. The cubic root of 21111792 is about 276.3811160039.

The spelling of 21111792 in words is "twenty-one million, one hundred eleven thousand, seven hundred ninety-two".