21253953792 has 144 divisors (see below), whose sum is σ = 60878103552. Its totient is φ = 6558351360.

The previous prime is 21253953767. The next prime is 21253953817. The reversal of 21253953792 is 29735935212.

It is an interprime number because it is at equal distance from previous prime (21253953767) and next prime (21253953817).

It is a Harshad number since it is a multiple of its sum of digits (48).

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, 783073 + ... + 809759.

It is an arithmetic number, because the mean of its divisors is an integer number (422764608).

Almost surely, 2^21253953792 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 21253953792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30439051776).

21253953792 is an abundant number, since it is smaller than the sum of its proper divisors (39624149760).

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

21253953792 is a wasteful number, since it uses less digits than its factorization.

21253953792 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26784 (or 26770 counting only the distinct ones).

The product of its digits is 1020600, while the sum is 48.

The spelling of 21253953792 in words is "twenty-one billion, two hundred fifty-three million, nine hundred fifty-three thousand, seven hundred ninety-two".