2176406820225 has 81 divisors (see below), whose sum is σ = 4285262722377. Its totient is φ = 1055109528000.

The previous prime is 2176406820179. The next prime is 2176406820227. The reversal of 2176406820225 is 5220286046712.

The square root of 2176406820225 is 1475265.

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

2176406820225 is a `hidden beast` number, since 2 + 17 + 6 + 406 + 8 + 2 + 0 + 225 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 876219201 + 2175530601024 = 29601^2 + 1474968^2 .

It is not a de Polignac number, because 2176406820225 - 2³⁷ = 2038967866753 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (2176406820227) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 243414255 + ... + 243423195.

Almost surely, 2^{2176406820225} is an apocalyptic number.

2176406820225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

2176406820225 is the 1475265-th square number.

2176406820225 is the 737633-rd centered octagonal number.

It is an amenable number.

2176406820225 is a deficient number, since it is larger than the sum of its proper divisors (2108855902152).

2176406820225 is an frugal number, since it uses more digits than its factorization.

2176406820225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17920 (or 8960 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 45.

The spelling of 2176406820225 in words is "two trillion, one hundred seventy-six billion, four hundred six million, eight hundred twenty thousand, two hundred twenty-five".