861135744677 has 4 divisors (see below), whose sum is σ = 927376955820. Its totient is φ = 794894533536.

The previous prime is 861135744649. The next prime is 861135744701. The reversal of 861135744677 is 776447531168.

It is a Cunningham number, because it is equal to 927974²+1.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 127387603396 + 733748141281 = 356914^2 + 856591^2 .

It is a cyclic number.

It is not a de Polignac number, because 861135744677 - 2¹² = 861135740581 is a prime.

It is a super-2 number, since 2×861135744677² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861135744607) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33120605552 + ... + 33120605577.

It is an arithmetic number, because the mean of its divisors is an integer number (231844238955).

Almost surely, 2^861135744677 is an apocalyptic number.

It is an amenable number.

861135744677 is a deficient number, since it is larger than the sum of its proper divisors (66241211143).

861135744677 is a wasteful number, since it uses less digits than its factorization.

861135744677 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66241211142.

The product of its digits is 23708160, while the sum is 59.

The spelling of 861135744677 in words is "eight hundred sixty-one billion, one hundred thirty-five million, seven hundred forty-four thousand, six hundred seventy-seven".