21142631536 has 80 divisors (see below), whose sum is σ = 46871625024. Its totient is φ = 9152335872.

The previous prime is 21142631507. The next prime is 21142631579. The reversal of 21142631536 is 63513624112.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1025845 + ... + 1046251.

Almost surely, 2^21142631536 is an apocalyptic number.

21142631536 is a gapful number since it is divisible by the number (26) 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 21142631536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23435812512).

21142631536 is an abundant number, since it is smaller than the sum of its proper divisors (25728993488).

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

21142631536 is a wasteful number, since it uses less digits than its factorization.

21142631536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20738 (or 20732 counting only the distinct ones).

The product of its digits is 25920, while the sum is 34.

The spelling of 21142631536 in words is "twenty-one billion, one hundred forty-two million, six hundred thirty-one thousand, five hundred thirty-six".