139693997 has 4 divisors (see below), whose sum is σ = 140530656. Its totient is φ = 138857340.

The previous prime is 139693993. The next prime is 139693999. The reversal of 139693997 is 799396931.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 799396931 = 557 ⋅1435183.

It is a cyclic number.

It is not a de Polignac number, because 139693997 - 2² = 139693993 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139693993) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 418079 + ... + 418412.

It is an arithmetic number, because the mean of its divisors is an integer number (35132664).

Almost surely, 2^139693997 is an apocalyptic number.

It is an amenable number.

139693997 is a deficient number, since it is larger than the sum of its proper divisors (836659).

139693997 is an equidigital number, since it uses as much as digits as its factorization.

139693997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 836658.

The product of its digits is 2480058, while the sum is 56.

The square root of 139693997 is about 11819.2215056661. The cubic root of 139693997 is about 518.8708202250.

The spelling of 139693997 in words is "one hundred thirty-nine million, six hundred ninety-three thousand, nine hundred ninety-seven".