139681999 has 2 divisors, whose sum is σ = 139682000. Its totient is φ = 139681998.

The previous prime is 139681937. The next prime is 139682021. The reversal of 139681999 is 999186931.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 139681999 - 2¹¹ = 139679951 is a prime.

It is a super-2 number, since 2×139681999² = 39022121689272002, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (139681799) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69840999 + 69841000.

It is an arithmetic number, because the mean of its divisors is an integer number (69841000).

Almost surely, 2^139681999 is an apocalyptic number.

139681999 is a deficient number, since it is larger than the sum of its proper divisors (1).

139681999 is an equidigital number, since it uses as much as digits as its factorization.

139681999 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 944784, while the sum is 55.

The square root of 139681999 is about 11818.7139317271. The cubic root of 139681999 is about 518.8559649211.

The spelling of 139681999 in words is "one hundred thirty-nine million, six hundred eighty-one thousand, nine hundred ninety-nine".