21253739921232 has 640 divisors, whose sum is σ = 70208682356736. Its totient is φ = 5391621881856.

The previous prime is 21253739921203. The next prime is 21253739921263. The reversal of 21253739921232 is 23212993735212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 3476807008 + ... + 3476813120.

Almost surely, 2^{21253739921232} 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 21253739921232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35104341178368).

21253739921232 is an abundant number, since it is smaller than the sum of its proper divisors (48954942435504).

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

21253739921232 is a wasteful number, since it uses less digits than its factorization.

21253739921232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6467 (or 6461 counting only the distinct ones).

The product of its digits is 2449440, while the sum is 51.

The spelling of 21253739921232 in words is "twenty-one trillion, two hundred fifty-three billion, seven hundred thirty-nine million, nine hundred twenty-one thousand, two hundred thirty-two".