138777901 has 2 divisors, whose sum is σ = 138777902. Its totient is φ = 138777900.

The previous prime is 138777889. The next prime is 138777911. The reversal of 138777901 is 109777831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 132848676 + 5929225 = 11526^2 + 2435^2 .

It is a cyclic number.

It is not a de Polignac number, because 138777901 - 2⁵ = 138777869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138777911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69388950 + 69388951.

It is an arithmetic number, because the mean of its divisors is an integer number (69388951).

Almost surely, 2^138777901 is an apocalyptic number.

It is an amenable number.

138777901 is a deficient number, since it is larger than the sum of its proper divisors (1).

138777901 is an equidigital number, since it uses as much as digits as its factorization.

138777901 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 74088, while the sum is 43.

The square root of 138777901 is about 11780.4032613489. The cubic root of 138777901 is about 517.7341014940.

The spelling of 138777901 in words is "one hundred thirty-eight million, seven hundred seventy-seven thousand, nine hundred one".