2151855 has 12 divisors (see below), whose sum is σ = 3729960. Its totient is φ = 1147632.

The previous prime is 2151847. The next prime is 2151869. The reversal of 2151855 is 5581512.

It is not a de Polignac number, because 2151855 - 2³ = 2151847 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 23865 + ... + 23954.

It is an arithmetic number, because the mean of its divisors is an integer number (310830).

2^2151855 is an apocalyptic number.

2151855 is a deficient number, since it is larger than the sum of its proper divisors (1578105).

2151855 is a wasteful number, since it uses less digits than its factorization.

2151855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47830 (or 47827 counting only the distinct ones).

The product of its digits is 2000, while the sum is 27.

The square root of 2151855 is about 1466.9202432307. The cubic root of 2151855 is about 129.1033964614.

The spelling of 2151855 in words is "two million, one hundred fifty-one thousand, eight hundred fifty-five".