139743561 has 32 divisors (see below), whose sum is σ = 201719808. Its totient is φ = 85821120.

The previous prime is 139743557. The next prime is 139743577. The reversal of 139743561 is 165347931.

It is not a de Polignac number, because 139743561 - 2² = 139743557 is a prime.

It is not an unprimeable number, because it can be changed into a prime (139743161) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 324016 + ... + 324446.

It is an arithmetic number, because the mean of its divisors is an integer number (6303744).

Almost surely, 2^139743561 is an apocalyptic number.

It is an amenable number.

139743561 is a deficient number, since it is larger than the sum of its proper divisors (61976247).

139743561 is a wasteful number, since it uses less digits than its factorization.

139743561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 621.

The product of its digits is 68040, while the sum is 39.

The square root of 139743561 is about 11821.3180737175. The cubic root of 139743561 is about 518.9321787967.

The spelling of 139743561 in words is "one hundred thirty-nine million, seven hundred forty-three thousand, five hundred sixty-one".