20551243521320 has 16 divisors (see below), whose sum is σ = 46240297923060. Its totient is φ = 8220497408512.

The previous prime is 20551243521251. The next prime is 20551243521331. The reversal of 20551243521320 is 2312534215502.

It can be written as a sum of positive squares in 2 ways, for example, as 17354006282596 + 3197237238724 = 4165814^2 + 1788082^2 .

It is a super-2 number, since 2×20551243521320² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 256890543977 + ... + 256890544056.

Almost surely, 2^{20551243521320} is an apocalyptic number.

20551243521320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20551243521320 is an abundant number, since it is smaller than the sum of its proper divisors (25689054401740).

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

20551243521320 is a wasteful number, since it uses less digits than its factorization.

20551243521320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 513781088044 (or 513781088040 counting only the distinct ones).

The product of its (nonzero) digits is 72000, while the sum is 35.

Adding to 20551243521320 its reverse (2312534215502), we get a palindrome (22863777736822).

The spelling of 20551243521320 in words is "twenty trillion, five hundred fifty-one billion, two hundred forty-three million, five hundred twenty-one thousand, three hundred twenty".