2155421171020 has 48 divisors (see below), whose sum is σ = 4874698055808. Its totient is φ = 795826563840.

The previous prime is 2155421170979. The next prime is 2155421171023. The reversal of 2155421171020 is 201711245512.

It is not an unprimeable number, because it can be changed into a prime (2155421171023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12325837 + ... + 12499483.

It is an arithmetic number, because the mean of its divisors is an integer number (101556209496).

Almost surely, 2^{2155421171020} is an apocalyptic number.

2155421171020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2155421171020 is an abundant number, since it is smaller than the sum of its proper divisors (2719276884788).

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

2155421171020 is a wasteful number, since it uses less digits than its factorization.

2155421171020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221410 (or 221408 counting only the distinct ones).

The product of its (nonzero) digits is 5600, while the sum is 31.

The spelling of 2155421171020 in words is "two trillion, one hundred fifty-five billion, four hundred twenty-one million, one hundred seventy-one thousand, twenty".