745727121365561 has 8 divisors (see below), whose sum is σ = 746450202057864. Its totient is φ = 745004115273600.

The previous prime is 745727121365509. The next prime is 745727121365591. The reversal of 745727121365561 is 165563121727547.

It can be written as a sum of positive squares in 4 ways, for example, as 8122956006400 + 737604165359161 = 2850080^2 + 27158869^2 .

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 745727121365561 - 2³⁰ = 745726047623737 is a prime.

It is a super-2 number, since 2×745727121365561² (a number of 31 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 = 745727121365494 and 745727121365503.

It is not an unprimeable number, because it can be changed into a prime (745727121365591) 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, 1362605 + ... + 38643381.

It is an arithmetic number, because the mean of its divisors is an integer number (93306275257233).

Almost surely, 2^{745727121365561} is an apocalyptic number.

It is an amenable number.

745727121365561 is a deficient number, since it is larger than the sum of its proper divisors (723080692303).

745727121365561 is a wasteful number, since it uses less digits than its factorization.

745727121365561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37300171.

The product of its digits is 74088000, while the sum is 62.

The spelling of 745727121365561 in words is "seven hundred forty-five trillion, seven hundred twenty-seven billion, one hundred twenty-one million, three hundred sixty-five thousand, five hundred sixty-one".