21326013240 has 96 divisors (see below), whose sum is σ = 74423454480. Its totient is φ = 4874515968.

The previous prime is 21326013229. The next prime is 21326013251. The reversal of 21326013240 is 4231062312.

It is an interprime number because it is at equal distance from previous prime (21326013229) and next prime (21326013251).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 21326013240.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1807557 + ... + 1819316.

Almost surely, 2^21326013240 is an apocalyptic number.

21326013240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21326013240 is an abundant number, since it is smaller than the sum of its proper divisors (53097441240).

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

21326013240 is a wasteful number, since it uses less digits than its factorization.

21326013240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3626901 (or 3626890 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

Adding to 21326013240 its reverse (4231062312), we get a palindrome (25557075552).

The spelling of 21326013240 in words is "twenty-one billion, three hundred twenty-six million, thirteen thousand, two hundred forty".