2154865881 has 8 divisors (see below), whose sum is σ = 3283605184. Its totient is φ = 1231351920.

The previous prime is 2154865871. The next prime is 2154865919. The reversal of 2154865881 is 1885684512.

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

It is not a de Polignac number, because 2154865881 - 2¹⁷ = 2154734809 is a prime.

It is a super-2 number, since 2×2154865881² = 9286893930195812322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2154865881.

It is not an unprimeable number, because it can be changed into a prime (2154865841) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51306310 + ... + 51306351.

It is an arithmetic number, because the mean of its divisors is an integer number (410450648).

Almost surely, 2^2154865881 is an apocalyptic number.

2154865881 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2154865881 is a deficient number, since it is larger than the sum of its proper divisors (1128739303).

2154865881 is a wasteful number, since it uses less digits than its factorization.

2154865881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102612671.

The product of its digits is 614400, while the sum is 48.

The square root of 2154865881 is about 46420.5329676427. The cubic root of 2154865881 is about 1291.6358233320.

The spelling of 2154865881 in words is "two billion, one hundred fifty-four million, eight hundred sixty-five thousand, eight hundred eighty-one".