2021556155 has 16 divisors (see below), whose sum is σ = 2460094464. Its totient is φ = 1594585440.

The previous prime is 2021556149. The next prime is 2021556169. The reversal of 2021556155 is 5516551202.

It is not a de Polignac number, because 2021556155 - 2¹⁴ = 2021539771 is a prime.

It is a Duffinian number.

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, 93740 + ... + 113270.

It is an arithmetic number, because the mean of its divisors is an integer number (153755904).

Almost surely, 2^2021556155 is an apocalyptic number.

2021556155 is a deficient number, since it is larger than the sum of its proper divisors (438538309).

2021556155 is a wasteful number, since it uses less digits than its factorization.

2021556155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19826.

The product of its (nonzero) digits is 15000, while the sum is 32.

The square root of 2021556155 is about 44961.7187727516. The cubic root of 2021556155 is about 1264.4313931287.

The spelling of 2021556155 in words is "two billion, twenty-one million, five hundred fifty-six thousand, one hundred fifty-five".