2156540 has 12 divisors (see below), whose sum is σ = 4528776. Its totient is φ = 862608.

The previous prime is 2156537. The next prime is 2156597. The reversal of 2156540 is 456512.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53894 + ... + 53933.

It is an arithmetic number, because the mean of its divisors is an integer number (377398).

2^2156540 is an apocalyptic number.

2156540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2156540 is an abundant number, since it is smaller than the sum of its proper divisors (2372236).

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

2156540 is a wasteful number, since it uses less digits than its factorization.

2156540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107836 (or 107834 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 2156540 is about 1468.5162579965. The cubic root of 2156540 is about 129.1970228109.

The spelling of 2156540 in words is "two million, one hundred fifty-six thousand, five hundred forty".