61775621791 has 8 divisors (see below), whose sum is σ = 66529693440. Its totient is φ = 57021850272.

The previous prime is 61775621767. The next prime is 61775621827. The reversal of 61775621791 is 19712657716.

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 61775621791 - 2⁹ = 61775621279 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 (61775621711) 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, 538050 + ... + 642688.

It is an arithmetic number, because the mean of its divisors is an integer number (8316211680).

Almost surely, 2^61775621791 is an apocalyptic number.

61775621791 is a deficient number, since it is larger than the sum of its proper divisors (4754071649).

61775621791 is a wasteful number, since it uses less digits than its factorization.

61775621791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150065.

The product of its digits is 1111320, while the sum is 52.

The spelling of 61775621791 in words is "sixty-one billion, seven hundred seventy-five million, six hundred twenty-one thousand, seven hundred ninety-one".