645736076077 has 4 divisors (see below), whose sum is σ = 648017829280. Its totient is φ = 643454322876.

The previous prime is 645736075979. The next prime is 645736076119. The reversal of 645736076077 is 770670637546.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645736076077 is a prime.

It is a super-2 number, since 2×645736076077² (a number of 24 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 (645736076177) 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, 1140876177 + ... + 1140876742.

It is an arithmetic number, because the mean of its divisors is an integer number (162004457320).

Almost surely, 2^645736076077 is an apocalyptic number.

It is an amenable number.

645736076077 is a deficient number, since it is larger than the sum of its proper divisors (2281753203).

645736076077 is a wasteful number, since it uses less digits than its factorization.

645736076077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2281753202.

The product of its (nonzero) digits is 31116960, while the sum is 58.

The spelling of 645736076077 in words is "six hundred forty-five billion, seven hundred thirty-six million, seventy-six thousand, seventy-seven".