21312269802 has 56 divisors (see below), whose sum is σ = 48108438720. Its totient is φ = 7077744360.

The previous prime is 21312269801. The next prime is 21312269813. The reversal of 21312269802 is 20896221312.

It is a happy number.

21312269802 is a `hidden beast` number, since 2 + 1 + 312 + 269 + 80 + 2 = 666.

It is a super-2 number, since 2×21312269802² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21312269801) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 368149 + ... + 422087.

Almost surely, 2^21312269802 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21312269802, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24054219360).

21312269802 is an abundant number, since it is smaller than the sum of its proper divisors (26796168918).

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

21312269802 is an equidigital number, since it uses as much as digits as its factorization.

21312269802 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54230 (or 54215 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The spelling of 21312269802 in words is "twenty-one billion, three hundred twelve million, two hundred sixty-nine thousand, eight hundred two".