2101949977 has 2 divisors, whose sum is σ = 2101949978. Its totient is φ = 2101949976.

The previous prime is 2101949903. The next prime is 2101950029. The reversal of 2101949977 is 7799491012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1892598016 + 209351961 = 43504^2 + 14469^2 .

It is a cyclic number.

It is not a de Polignac number, because 2101949977 - 2⁷ = 2101949849 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2101949977.

It is not a weakly prime, because it can be changed into another prime (2101949677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1050974988 + 1050974989.

It is an arithmetic number, because the mean of its divisors is an integer number (1050974989).

Almost surely, 2^2101949977 is an apocalyptic number.

It is an amenable number.

2101949977 is a deficient number, since it is larger than the sum of its proper divisors (1).

2101949977 is an equidigital number, since it uses as much as digits as its factorization.

2101949977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 285768, while the sum is 49.

The square root of 2101949977 is about 45847.0280061860. The cubic root of 2101949977 is about 1280.9754074342.

The spelling of 2101949977 in words is "two billion, one hundred one million, nine hundred forty-nine thousand, nine hundred seventy-seven".