2151816 has 16 divisors (see below), whose sum is σ = 5379600. Its totient is φ = 717264.

The previous prime is 2151791. The next prime is 2151817. The reversal of 2151816 is 6181512.

It is a Harshad number since it is a multiple of its sum of digits (24), and also a Moran number because the ratio is a prime number: 89659 = 2151816 / (2 + 1 + 5 + 1 + 8 + 1 + 6).

It is not an unprimeable number, because it can be changed into a prime (2151817) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 44806 + ... + 44853.

It is an arithmetic number, because the mean of its divisors is an integer number (336225).

2^2151816 is an apocalyptic number.

It is an amenable number.

2151816 is an abundant number, since it is smaller than the sum of its proper divisors (3227784).

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

2151816 is a wasteful number, since it uses less digits than its factorization.

2151816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89668 (or 89664 counting only the distinct ones).

The product of its digits is 480, while the sum is 24.

The square root of 2151816 is about 1466.9069500142. The cubic root of 2151816 is about 129.1026165045.

The spelling of 2151816 in words is "two million, one hundred fifty-one thousand, eight hundred sixteen".