139139969 has 2 divisors, whose sum is σ = 139139970. Its totient is φ = 139139968.

The previous prime is 139139953. The next prime is 139139989. The reversal of 139139969 is 969931931.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 72880369 + 66259600 = 8537^2 + 8140^2 .

It is a cyclic number.

It is not a de Polignac number, because 139139969 - 2⁴ = 139139953 is a prime.

It is a super-2 number, since 2×139139969² = 38719861946641922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (139139909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69569984 + 69569985.

It is an arithmetic number, because the mean of its divisors is an integer number (69569985).

Almost surely, 2^139139969 is an apocalyptic number.

It is an amenable number.

139139969 is a deficient number, since it is larger than the sum of its proper divisors (1).

139139969 is an equidigital number, since it uses as much as digits as its factorization.

139139969 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 354294, while the sum is 50.

The square root of 139139969 is about 11795.7606367712. The cubic root of 139139969 is about 518.1839621790.

The spelling of 139139969 in words is "one hundred thirty-nine million, one hundred thirty-nine thousand, nine hundred sixty-nine".