61079991 has 16 divisors (see below), whose sum is σ = 93600000. Its totient is φ = 34705728.

The previous prime is 61079989. The next prime is 61079999. The reversal of 61079991 is 19997016.

It is not a de Polignac number, because 61079991 - 2¹ = 61079989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61079999) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4366 + ... + 11883.

It is an arithmetic number, because the mean of its divisors is an integer number (5850000).

Almost surely, 2^61079991 is an apocalyptic number.

61079991 is a deficient number, since it is larger than the sum of its proper divisors (32520009).

61079991 is a wasteful number, since it uses less digits than its factorization.

61079991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16438.

The product of its (nonzero) digits is 30618, while the sum is 42.

The square root of 61079991 is about 7815.3688972434. The cubic root of 61079991 is about 393.8217111012.

It can be divided in two parts, 610 and 79991, that added together give a triangular number (80601 = T₄₀₁).

The spelling of 61079991 in words is "sixty-one million, seventy-nine thousand, nine hundred ninety-one".