2151556 has 24 divisors (see below), whose sum is σ = 4154976. Its totient is φ = 966720.

The previous prime is 2151533. The next prime is 2151563. The reversal of 2151556 is 6551512.

It is a super-2 number, since 2×2151556² = 9258386442272, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 2151556.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4480 + ... + 4936.

It is an arithmetic number, because the mean of its divisors is an integer number (173124).

2^2151556 is an apocalyptic number.

It is an amenable number.

2151556 is a deficient number, since it is larger than the sum of its proper divisors (2003420).

2151556 is a wasteful number, since it uses less digits than its factorization.

2151556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 579 (or 577 counting only the distinct ones).

The product of its digits is 1500, while the sum is 25.

The square root of 2151556 is about 1466.8183254923. The cubic root of 2151556 is about 129.0974165505.

It can be divided in two parts, 215 and 1556, that added together give a palindrome (1771).

The spelling of 2151556 in words is "two million, one hundred fifty-one thousand, five hundred fifty-six".