2166437025 has 81 divisors (see below), whose sum is σ = 4056657241. Its totient is φ = 1105164480.

The previous prime is 2166436969. The next prime is 2166437081. The reversal of 2166437025 is 5207346612.

The square root of 2166437025 is 46545.

It is a perfect power (a square), and thus also a powerful number.

2166437025 is a `hidden beast` number, since 2 + 1 + 6 + 643 + 7 + 0 + 2 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (2166436969) and next prime (2166437081).

It can be written as a sum of positive squares in 4 ways, for example, as 29778849 + 2136658176 = 5457^2 + 46224^2 .

It is not a de Polignac number, because 2166437025 - 2¹⁵ = 2166404257 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 20247022 + ... + 20247128.

Almost surely, 2^2166437025 is an apocalyptic number.

2166437025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

2166437025 is the 46545-th square number.

2166437025 is the 23273-rd centered octagonal number.

It is an amenable number.

2166437025 is a deficient number, since it is larger than the sum of its proper divisors (1890220216).

2166437025 is a wasteful number, since it uses less digits than its factorization.

2166437025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288 (or 144 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 36.

The cubic root of 2166437025 is about 1293.9436285142.

Multiplying 2166437025 by its sum of digits (36), we get a square (77991732900 = 279270²).

The spelling of 2166437025 in words is "two billion, one hundred sixty-six million, four hundred thirty-seven thousand, twenty-five".