21236267910 has 256 divisors, whose sum is σ = 63811722240. Its totient is φ = 4470036480.

The previous prime is 21236267891. The next prime is 21236267933. The reversal of 21236267910 is 1976263212.

It is a Harshad number since it is a multiple of its sum of digits (39).

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, 12324309 + ... + 12326031.

It is an arithmetic number, because the mean of its divisors is an integer number (249264540).

Almost surely, 2^21236267910 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21236267910, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31905861120).

21236267910 is an abundant number, since it is smaller than the sum of its proper divisors (42575454330).

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

21236267910 is a wasteful number, since it uses less digits than its factorization.

21236267910 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1800 (or 1774 counting only the distinct ones).

The product of its (nonzero) digits is 54432, while the sum is 39.

The spelling of 21236267910 in words is "twenty-one billion, two hundred thirty-six million, two hundred sixty-seven thousand, nine hundred ten".