168075380721 has 16 divisors (see below), whose sum is σ = 227148054336. Its totient is φ = 110530618176.

The previous prime is 168075380713. The next prime is 168075380731. The reversal of 168075380721 is 127083570861.

It is a happy number.

It is not a de Polignac number, because 168075380721 - 2³ = 168075380713 is a prime.

It is not an unprimeable number, because it can be changed into a prime (168075380731) 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, 354250 + ... + 679443.

It is an arithmetic number, because the mean of its divisors is an integer number (14196753396).

Almost surely, 2^168075380721 is an apocalyptic number.

It is an amenable number.

168075380721 is a deficient number, since it is larger than the sum of its proper divisors (59072673615).

168075380721 is a wasteful number, since it uses less digits than its factorization.

168075380721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1034432.

The product of its (nonzero) digits is 564480, while the sum is 48.

The spelling of 168075380721 in words is "one hundred sixty-eight billion, seventy-five million, three hundred eighty thousand, seven hundred twenty-one".