139225991 has 4 divisors (see below), whose sum is σ = 143717184. Its totient is φ = 134734800.

The previous prime is 139225987. The next prime is 139226011. The reversal of 139225991 is 199522931.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 139225991 - 2² = 139225987 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 (139221991) 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 in 3 ways as a sum of consecutive naturals, for example, 2245550 + ... + 2245611.

It is an arithmetic number, because the mean of its divisors is an integer number (35929296).

Almost surely, 2^139225991 is an apocalyptic number.

139225991 is a deficient number, since it is larger than the sum of its proper divisors (4491193).

139225991 is an equidigital number, since it uses as much as digits as its factorization.

139225991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4491192.

The product of its digits is 43740, while the sum is 41.

The square root of 139225991 is about 11799.4063833737. The cubic root of 139225991 is about 518.2907276618.

The spelling of 139225991 in words is "one hundred thirty-nine million, two hundred twenty-five thousand, nine hundred ninety-one".