7745445257891 has 16 divisors (see below), whose sum is σ = 8484348354048. Its totient is φ = 7012344780000.

The previous prime is 7745445257801. The next prime is 7745445257909. The reversal of 7745445257891 is 1987525445477.

It is a cyclic number.

It is not a de Polignac number, because 7745445257891 - 2³⁴ = 7728265388707 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7745445257801) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21420005 + ... + 21778601.

It is an arithmetic number, because the mean of its divisors is an integer number (530271772128).

Almost surely, 2^{7745445257891} is an apocalyptic number.

7745445257891 is a deficient number, since it is larger than the sum of its proper divisors (738903096157).

7745445257891 is a wasteful number, since it uses less digits than its factorization.

7745445257891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 366682.

The product of its digits is 395136000, while the sum is 68.

The spelling of 7745445257891 in words is "seven trillion, seven hundred forty-five billion, four hundred forty-five million, two hundred fifty-seven thousand, eight hundred ninety-one".