138785961 has 4 divisors (see below), whose sum is σ = 185047952. Its totient is φ = 92523972.

The previous prime is 138785957. The next prime is 138785993. The reversal of 138785961 is 169587831.

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.

It is not a de Polignac number, because 138785961 - 2² = 138785957 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 138785961.

It is not an unprimeable number, because it can be changed into a prime (138786961) 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, 23130991 + ... + 23130996.

It is an arithmetic number, because the mean of its divisors is an integer number (46261988).

Almost surely, 2^138785961 is an apocalyptic number.

It is an amenable number.

138785961 is a deficient number, since it is larger than the sum of its proper divisors (46261991).

138785961 is an equidigital number, since it uses as much as digits as its factorization.

138785961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46261990.

The product of its digits is 362880, while the sum is 48.

The square root of 138785961 is about 11780.7453499344. The cubic root of 138785961 is about 517.7441243580.

The spelling of 138785961 in words is "one hundred thirty-eight million, seven hundred eighty-five thousand, nine hundred sixty-one".