168404357641 has 9 divisors (see below), whose sum is σ = 182360791431. Its totient is φ = 155445251832.

The previous prime is 168404357603. The next prime is 168404357647. The reversal of 168404357641 is 146753404861.

The square root of 168404357641 is 410371.

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., 24911887225 + 143492470416 = 157835^2 + 378804^2 .

It is not a de Polignac number, because 168404357641 - 2⁹ = 168404357129 is a prime.

It is not an unprimeable number, because it can be changed into a prime (168404357647) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 5319040 + ... + 5350606.

It is an arithmetic number, because the mean of its divisors is an integer number (20262310159).

Almost surely, 2^168404357641 is an apocalyptic number.

168404357641 is the 410371-st square number.

168404357641 is the 205186-th centered octagonal number.

It is an amenable number.

168404357641 is a deficient number, since it is larger than the sum of its proper divisors (13956433790).

168404357641 is an frugal number, since it uses more digits than its factorization.

168404357641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63160 (or 31580 counting only the distinct ones).

The product of its (nonzero) digits is 1935360, while the sum is 49.

Multiplying 168404357641 by its sum of digits (49), we get a square (8251813524409 = 2872597²).

The spelling of 168404357641 in words is "one hundred sixty-eight billion, four hundred four million, three hundred fifty-seven thousand, six hundred forty-one".