8391166356001 has 81 divisors (see below), whose sum is σ = 10228162970739. Its totient is φ = 6875728173600.

The previous prime is 8391166355993. The next prime is 8391166356007. The reversal of 8391166356001 is 1006536611938.

The square root of 8391166356001 is 2896751.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 1241296798225 + 7149869557776 = 1114135^2 + 2673924^2 .

It is not a de Polignac number, because 8391166356001 - 2³ = 8391166355993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8391166356007) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 19469063256 + ... + 19469063686.

Almost surely, 2^{8391166356001} is an apocalyptic number.

8391166356001 is the 2896751-st square number.

8391166356001 is the 1448376-th centered octagonal number.

It is an amenable number.

8391166356001 is a deficient number, since it is larger than the sum of its proper divisors (1836996614738).

8391166356001 is an equidigital number, since it uses as much as digits as its factorization.

8391166356001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1004 (or 502 counting only the distinct ones).

The product of its (nonzero) digits is 699840, while the sum is 49.

Multiplying 8391166356001 by its sum of digits (49), we get a square (411167151444049 = 20277257²).

The spelling of 8391166356001 in words is "eight trillion, three hundred ninety-one billion, one hundred sixty-six million, three hundred fifty-six thousand, one".