20518690501900 has 36 divisors (see below), whose sum is σ = 45611547627240. Its totient is φ = 8007293852800.

The previous prime is 20518690501819. The next prime is 20518690501979. The reversal of 20518690501900 is 910509681502.

It is a super-2 number, since 2×20518690501900² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2502275230 + ... + 2502283429.

It is an arithmetic number, because the mean of its divisors is an integer number (1266987434090).

Almost surely, 2^{20518690501900} is an apocalyptic number.

20518690501900 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20518690501900 is an abundant number, since it is smaller than the sum of its proper divisors (25092857125340).

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

20518690501900 is a wasteful number, since it uses less digits than its factorization.

20518690501900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5004558714 (or 5004558707 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 46.

The spelling of 20518690501900 in words is "twenty trillion, five hundred eighteen billion, six hundred ninety million, five hundred one thousand, nine hundred".