61986491 has 8 divisors (see below), whose sum is σ = 71504640. Its totient is φ = 52634088.

The previous prime is 61986487. The next prime is 61986499. The reversal of 61986491 is 19468916.

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 61986491 - 2² = 61986487 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61986499) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40631 + ... + 42128.

It is an arithmetic number, because the mean of its divisors is an integer number (8938080).

Almost surely, 2^61986491 is an apocalyptic number.

61986491 is a deficient number, since it is larger than the sum of its proper divisors (9518149).

61986491 is a wasteful number, since it uses less digits than its factorization.

61986491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82873.

The product of its digits is 93312, while the sum is 44.

The square root of 61986491 is about 7873.1500049218. The cubic root of 61986491 is about 395.7604130963.

The spelling of 61986491 in words is "sixty-one million, nine hundred eighty-six thousand, four hundred ninety-one".