137725661 has 4 divisors (see below), whose sum is σ = 144974400. Its totient is φ = 130476924.

The previous prime is 137725649. The next prime is 137725663. The reversal of 137725661 is 166527731.

137725661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, and also an emirpimes, since its reverse is a distinct semiprime: 166527731 = 71 ⋅2345461.

It is a cyclic number.

It is not a de Polignac number, because 137725661 - 2⁶ = 137725597 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 (137725663) 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, 3624341 + ... + 3624378.

It is an arithmetic number, because the mean of its divisors is an integer number (36243600).

Almost surely, 2^137725661 is an apocalyptic number.

It is an amenable number.

137725661 is a deficient number, since it is larger than the sum of its proper divisors (7248739).

137725661 is an equidigital number, since it uses as much as digits as its factorization.

137725661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7248738.

The product of its digits is 52920, while the sum is 38.

The square root of 137725661 is about 11735.6576722398. The cubic root of 137725661 is about 516.4222614189.

The spelling of 137725661 in words is "one hundred thirty-seven million, seven hundred twenty-five thousand, six hundred sixty-one".