21263572000 has 144 divisors (see below), whose sum is σ = 57427185816. Its totient is φ = 7732032000.

The previous prime is 21263571997. The next prime is 21263572039. The reversal of 21263572000 is 27536212.

It can be written as a sum of positive squares in 4 ways, for example, as 1599680016 + 19663891984 = 39996^2 + 140228^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21263572000.

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, 462034 + ... + 505966.

Almost surely, 2^21263572000 is an apocalyptic number.

21263572000 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 21263572000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28713592908).

21263572000 is an abundant number, since it is smaller than the sum of its proper divisors (36163613816).

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

21263572000 is a wasteful number, since it uses less digits than its factorization.

21263572000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43980 (or 43951 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 28.

It can be divided in two parts, 212635 and 72000, that added together give a triangular number (284635 = T₇₅₄).

The spelling of 21263572000 in words is "twenty-one billion, two hundred sixty-three million, five hundred seventy-two thousand".