61581655 has 8 divisors (see below), whose sum is σ = 76281984. Its totient is φ = 47676000.

The previous prime is 61581623. The next prime is 61581671. The reversal of 61581655 is 55618516.

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

It is not a de Polignac number, because 61581655 - 2⁵ = 61581623 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 198496 + ... + 198805.

It is an arithmetic number, because the mean of its divisors is an integer number (9535248).

Almost surely, 2^61581655 is an apocalyptic number.

61581655 is a deficient number, since it is larger than the sum of its proper divisors (14700329).

61581655 is a wasteful number, since it uses less digits than its factorization.

61581655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 397337.

The product of its digits is 36000, while the sum is 37.

The square root of 61581655 is about 7847.3979763996. The cubic root of 61581655 is about 394.8969554421.

The spelling of 61581655 in words is "sixty-one million, five hundred eighty-one thousand, six hundred fifty-five".