2545440661 has 2 divisors, whose sum is σ = 2545440662. Its totient is φ = 2545440660.

The previous prime is 2545440649. The next prime is 2545440671. The reversal of 2545440661 is 1660445452.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2024460036 + 520980625 = 44994^2 + 22825^2 .

It is a cyclic number.

It is not a de Polignac number, because 2545440661 - 2⁵ = 2545440629 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2545440661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2545440671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1272720330 + 1272720331.

It is an arithmetic number, because the mean of its divisors is an integer number (1272720331).

Almost surely, 2^2545440661 is an apocalyptic number.

It is an amenable number.

2545440661 is a deficient number, since it is larger than the sum of its proper divisors (1).

2545440661 is an equidigital number, since it uses as much as digits as its factorization.

2545440661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 115200, while the sum is 37.

The square root of 2545440661 is about 50452.3603114859. The cubic root of 2545440661 is about 1365.3824796404.

The spelling of 2545440661 in words is "two billion, five hundred forty-five million, four hundred forty thousand, six hundred sixty-one".