2156481 has 12 divisors (see below), whose sum is σ = 3279120. Its totient is φ = 1361880.

The previous prime is 2156461. The next prime is 2156491. The reversal of 2156481 is 1846512.

2156481 is a `hidden beast` number, since 2 + 15 + 648 + 1 = 666.

It is not a de Polignac number, because 2156481 - 2⁶ = 2156417 is a prime.

It is a super-2 number, since 2×2156481² = 9300820606722, which contains 22 as substring.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (2156461) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6135 + ... + 6476.

It is an arithmetic number, because the mean of its divisors is an integer number (273260).

2^2156481 is an apocalyptic number.

It is an amenable number.

2156481 is a deficient number, since it is larger than the sum of its proper divisors (1122639).

2156481 is a wasteful number, since it uses less digits than its factorization.

2156481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12636 (or 12633 counting only the distinct ones).

The product of its digits is 1920, while the sum is 27.

The square root of 2156481 is about 1468.4961695558. The cubic root of 2156481 is about 129.1958445819.

The spelling of 2156481 in words is "two million, one hundred fifty-six thousand, four hundred eighty-one".