61331591 has 8 divisors (see below), whose sum is σ = 62190000. Its totient is φ = 60477120.

The previous prime is 61331587. The next prime is 61331623. The reversal of 61331591 is 19513316.

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 61331591 - 2² = 61331587 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 (61331551) 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, 43721 + ... + 45101.

It is an arithmetic number, because the mean of its divisors is an integer number (7773750).

Almost surely, 2^61331591 is an apocalyptic number.

61331591 is a deficient number, since it is larger than the sum of its proper divisors (858409).

61331591 is a wasteful number, since it uses less digits than its factorization.

61331591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1969.

The product of its digits is 2430, while the sum is 29.

The square root of 61331591 is about 7831.4488442433. The cubic root of 61331591 is about 394.3617122849.

The spelling of 61331591 in words is "sixty-one million, three hundred thirty-one thousand, five hundred ninety-one".