21526360640 has 112 divisors (see below), whose sum is σ = 51857891712. Its totient is φ = 8510631936.

The previous prime is 21526360633. The next prime is 21526360663. The reversal of 21526360640 is 4606362512.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21526360640.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11528987 + ... + 11530853.

Almost surely, 2^21526360640 is an apocalyptic number.

21526360640 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 21526360640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25928945856).

21526360640 is an abundant number, since it is smaller than the sum of its proper divisors (30331531072).

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

21526360640 is a wasteful number, since it uses less digits than its factorization.

21526360640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2284 (or 2274 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 35.

The spelling of 21526360640 in words is "twenty-one billion, five hundred twenty-six million, three hundred sixty thousand, six hundred forty".