61777791 has 6 divisors (see below), whose sum is σ = 89234600. Its totient is φ = 41185188.

The previous prime is 61777789. The next prime is 61777831. The reversal of 61777791 is 19777716.

It is not a de Polignac number, because 61777791 - 2¹ = 61777789 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 (61777741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3432091 + ... + 3432108.

Almost surely, 2^61777791 is an apocalyptic number.

61777791 is a deficient number, since it is larger than the sum of its proper divisors (27456809).

61777791 is a wasteful number, since it uses less digits than its factorization.

61777791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6864205 (or 6864202 counting only the distinct ones).

The product of its digits is 129654, while the sum is 45.

The square root of 61777791 is about 7859.8849228217. The cubic root of 61777791 is about 395.3157567084.

The spelling of 61777791 in words is "sixty-one million, seven hundred seventy-seven thousand, seven hundred ninety-one".