139500661 has 4 divisors (see below), whose sum is σ = 140519052. Its totient is φ = 138482272.

The previous prime is 139500583. The next prime is 139500671. The reversal of 139500661 is 166005931.

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 85932900 + 53567761 = 9270^2 + 7319^2 .

It is a cyclic number.

It is not a de Polignac number, because 139500661 - 2⁷ = 139500533 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139500671) 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, 508990 + ... + 509263.

It is an arithmetic number, because the mean of its divisors is an integer number (35129763).

Almost surely, 2^139500661 is an apocalyptic number.

It is an amenable number.

139500661 is a deficient number, since it is larger than the sum of its proper divisors (1018391).

139500661 is a wasteful number, since it uses less digits than its factorization.

139500661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1018390.

The product of its (nonzero) digits is 4860, while the sum is 31.

The square root of 139500661 is about 11811.0397933459. The cubic root of 139500661 is about 518.6313379140.

The spelling of 139500661 in words is "one hundred thirty-nine million, five hundred thousand, six hundred sixty-one".