21436718732 has 24 divisors (see below), whose sum is σ = 44072695632. Its totient is φ = 8994427200.

The previous prime is 21436718731. The next prime is 21436718741. The reversal of 21436718732 is 23781763412.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is not an unprimeable number, because it can be changed into a prime (21436718731) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18737819 + ... + 18738962.

It is an arithmetic number, because the mean of its divisors is an integer number (1836362318).

Almost surely, 2^21436718732 is an apocalyptic number.

21436718732 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21436718732 is an abundant number, since it is smaller than the sum of its proper divisors (22635976900).

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

21436718732 is a wasteful number, since it uses less digits than its factorization.

21436718732 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37476809 (or 37476807 counting only the distinct ones).

The product of its digits is 338688, while the sum is 44.

The spelling of 21436718732 in words is "twenty-one billion, four hundred thirty-six million, seven hundred eighteen thousand, seven hundred thirty-two".