61991163 has 40 divisors (see below), whose sum is σ = 105624288. Its totient is φ = 35894016.

The previous prime is 61991159. The next prime is 61991173. The reversal of 61991163 is 36119916.

It is not a de Polignac number, because 61991163 - 2² = 61991159 is a prime.

It is not an unprimeable number, because it can be changed into a prime (61991173) 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 39 ways as a sum of consecutive naturals, for example, 16170 + ... + 19632.

Almost surely, 2^61991163 is an apocalyptic number.

61991163 is a deficient number, since it is larger than the sum of its proper divisors (43633125).

61991163 is a wasteful number, since it uses less digits than its factorization.

61991163 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3505 (or 3496 counting only the distinct ones).

The product of its digits is 8748, while the sum is 36.

The square root of 61991163 is about 7873.4467039537. The cubic root of 61991163 is about 395.7703558336.

The spelling of 61991163 in words is "sixty-one million, nine hundred ninety-one thousand, one hundred sixty-three".