61640137 has 8 divisors (see below), whose sum is σ = 66475080. Its totient is φ = 56818560.

The previous prime is 61640129. The next prime is 61640153. The reversal of 61640137 is 73104616.

It can be written as a sum of positive squares in 4 ways, for example, as 8874441 + 52765696 = 2979^2 + 7264^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 61640137 - 2³ = 61640129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61640107) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7587 + ... + 13447.

It is an arithmetic number, because the mean of its divisors is an integer number (8309385).

Almost surely, 2^61640137 is an apocalyptic number.

It is an amenable number.

61640137 is a deficient number, since it is larger than the sum of its proper divisors (4834943).

61640137 is a wasteful number, since it uses less digits than its factorization.

61640137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6683.

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 61640137 is about 7851.1232954272. The cubic root of 61640137 is about 395.0219226203.

The spelling of 61640137 in words is "sixty-one million, six hundred forty thousand, one hundred thirty-seven".