2166551157021 has 8 divisors (see below), whose sum is σ = 2889125644800. Its totient is φ = 1444172053632.

The previous prime is 2166551156999. The next prime is 2166551157061. The reversal of 2166551157021 is 1207511556612.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2166551157021 - 2⁷ = 2166551156893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2166551157061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48820221 + ... + 48864578.

It is an arithmetic number, because the mean of its divisors is an integer number (361140705600).

Almost surely, 2^{2166551157021} is an apocalyptic number.

It is an amenable number.

2166551157021 is a deficient number, since it is larger than the sum of its proper divisors (722574487779).

2166551157021 is an equidigital number, since it uses as much as digits as its factorization.

2166551157021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97692195.

The product of its (nonzero) digits is 126000, while the sum is 42.

The spelling of 2166551157021 in words is "two trillion, one hundred sixty-six billion, five hundred fifty-one million, one hundred fifty-seven thousand, twenty-one".