139094561 has 4 divisors (see below), whose sum is σ = 147276612. Its totient is φ = 130912512.

The previous prime is 139094537. The next prime is 139094587. The reversal of 139094561 is 165490931.

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

It can be written as a sum of positive squares in 2 ways, for example, as 69472225 + 69622336 = 8335^2 + 8344^2 .

It is a de Polignac number, because none of the positive numbers 2^k-139094561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (139094531) 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, 4091000 + ... + 4091033.

It is an arithmetic number, because the mean of its divisors is an integer number (36819153).

Almost surely, 2^139094561 is an apocalyptic number.

It is an amenable number.

139094561 is a deficient number, since it is larger than the sum of its proper divisors (8182051).

139094561 is an equidigital number, since it uses as much as digits as its factorization.

139094561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8182050.

The product of its (nonzero) digits is 29160, while the sum is 38.

The square root of 139094561 is about 11793.8357204092. The cubic root of 139094561 is about 518.1275866755.

The spelling of 139094561 in words is "one hundred thirty-nine million, ninety-four thousand, five hundred sixty-one".