21155143645104 has 80 divisors (see below), whose sum is σ = 62655071985408. Its totient is φ = 6025259448576.

The previous prime is 21155143645087. The next prime is 21155143645169. The reversal of 21155143645104 is 40154634155112.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 99202222 + ... + 99415245.

Almost surely, 2^{21155143645104} is an apocalyptic number.

21155143645104 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21155143645104 is an abundant number, since it is smaller than the sum of its proper divisors (41499928340304).

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

21155143645104 is a wasteful number, since it uses less digits than its factorization.

21155143645104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198617802 (or 198617796 counting only the distinct ones).

The product of its (nonzero) digits is 288000, while the sum is 42.

The spelling of 21155143645104 in words is "twenty-one trillion, one hundred fifty-five billion, one hundred forty-three million, six hundred forty-five thousand, one hundred four".