2145989977 has 2 divisors, whose sum is σ = 2145989978. Its totient is φ = 2145989976.

The previous prime is 2145989971. The next prime is 2145989987. The reversal of 2145989977 is 7799895412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1973225241 + 172764736 = 44421^2 + 13144^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2145989977 is a prime.

It is not a weakly prime, because it can be changed into another prime (2145989971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1072994988 + 1072994989.

It is an arithmetic number, because the mean of its divisors is an integer number (1072994989).

Almost surely, 2^2145989977 is an apocalyptic number.

It is an amenable number.

2145989977 is a deficient number, since it is larger than the sum of its proper divisors (1).

2145989977 is an equidigital number, since it uses as much as digits as its factorization.

2145989977 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11430720, while the sum is 61.

The square root of 2145989977 is about 46324.8311060062. The cubic root of 2145989977 is about 1289.8599645679.

The spelling of 2145989977 in words is "two billion, one hundred forty-five million, nine hundred eighty-nine thousand, nine hundred seventy-seven".