745657721761 has 8 divisors (see below), whose sum is σ = 754152827400. Its totient is φ = 737165214720.

The previous prime is 745657721663. The next prime is 745657721777. The reversal of 745657721761 is 167127756547.

It can be written as a sum of positive squares in 4 ways, for example, as 168361681761 + 577296040000 = 410319^2 + 759800^2 .

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 745657721761 - 2¹¹ = 745657719713 is a prime.

It is a super-2 number, since 2×745657721761² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 745657721696 and 745657721705.

It is not an unprimeable number, because it can be changed into a prime (745657731761) 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, 69556 + ... + 1223173.

It is an arithmetic number, because the mean of its divisors is an integer number (94269103425).

Almost surely, 2^745657721761 is an apocalyptic number.

It is an amenable number.

745657721761 is a deficient number, since it is larger than the sum of its proper divisors (8495105639).

745657721761 is a wasteful number, since it uses less digits than its factorization.

745657721761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1299299.

The product of its digits is 17287200, while the sum is 58.

The spelling of 745657721761 in words is "seven hundred forty-five billion, six hundred fifty-seven million, seven hundred twenty-one thousand, seven hundred sixty-one".