21821231599504 has 10 divisors (see below), whose sum is σ = 42278636224070. Its totient is φ = 10910615799744.

The previous prime is 21821231599493. The next prime is 21821231599507. The reversal of 21821231599504 is 40599513212812.

It can be written as a sum of positive squares in only one way, i.e., 15467545094400 + 6353686505104 = 3932880^2 + 2520652^2 .

It is a super-2 number, since 2×21821231599504² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21821231599507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 681913487469 + ... + 681913487500.

It is an arithmetic number, because the mean of its divisors is an integer number (4227863622407).

Almost surely, 2^{21821231599504} is an apocalyptic number.

It is an amenable number.

21821231599504 is a deficient number, since it is larger than the sum of its proper divisors (20457404624566).

21821231599504 is a wasteful number, since it uses less digits than its factorization.

21821231599504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1363826974977 (or 1363826974971 counting only the distinct ones).

The product of its (nonzero) digits is 1555200, while the sum is 52.

The spelling of 21821231599504 in words is "twenty-one trillion, eight hundred twenty-one billion, two hundred thirty-one million, five hundred ninety-nine thousand, five hundred four".