21432012140 has 96 divisors (see below), whose sum is σ = 56668889088. Its totient is φ = 6613920000.

The previous prime is 21432012097. The next prime is 21432012157. The reversal of 21432012140 is 4121023412.

It is a super-2 number, since 2×21432012140² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 86645 + ... + 224435.

It is an arithmetic number, because the mean of its divisors is an integer number (590300928).

Almost surely, 2^21432012140 is an apocalyptic number.

21432012140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21432012140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28334444544).

21432012140 is an abundant number, since it is smaller than the sum of its proper divisors (35236876948).

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

21432012140 is a wasteful number, since it uses less digits than its factorization.

21432012140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137919 (or 137917 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21432012140 its reverse (4121023412), we get a palindrome (25553035552).

The spelling of 21432012140 in words is "twenty-one billion, four hundred thirty-two million, twelve thousand, one hundred forty".