138785869 has 2 divisors, whose sum is σ = 138785870. Its totient is φ = 138785868.

The previous prime is 138785863. The next prime is 138785923. The reversal of 138785869 is 968587831.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 92409769 + 46376100 = 9613^2 + 6810^2 .

It is a cyclic number.

It is not a de Polignac number, because 138785869 - 2¹³ = 138777677 is a prime.

It is a super-2 number, since 2×138785869² = 38523034868170322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138785863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69392934 + 69392935.

It is an arithmetic number, because the mean of its divisors is an integer number (69392935).

Almost surely, 2^138785869 is an apocalyptic number.

It is an amenable number.

138785869 is a deficient number, since it is larger than the sum of its proper divisors (1).

138785869 is an equidigital number, since it uses as much as digits as its factorization.

138785869 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2903040, while the sum is 55.

The square root of 138785869 is about 11780.7414452572. The cubic root of 138785869 is about 517.7440099553.

The spelling of 138785869 in words is "one hundred thirty-eight million, seven hundred eighty-five thousand, eight hundred sixty-nine".