21231553241600 has 120 divisors (see below), whose sum is σ = 56649203997540. Its totient is φ = 7839342673920.

The previous prime is 21231553241581. The next prime is 21231553241603. The reversal of 21231553241600 is 614235513212.

It can be written as a sum of positive squares in 6 ways, for example, as 2209813063936 + 19021740177664 = 1486544^2 + 4361392^2 .

It is not an unprimeable number, because it can be changed into a prime (21231553241603) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 63630335 + ... + 63963134.

Almost surely, 2^{21231553241600} is an apocalyptic number.

21231553241600 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21231553241600 is an abundant number, since it is smaller than the sum of its proper divisors (35417650755940).

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

21231553241600 is a wasteful number, since it uses less digits than its factorization.

21231553241600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127593510 (or 127593489 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 35.

Adding to 21231553241600 its reverse (614235513212), we get a palindrome (21845788754812).

The spelling of 21231553241600 in words is "twenty-one trillion, two hundred thirty-one billion, five hundred fifty-three million, two hundred forty-one thousand, six hundred".