168021208257 has 32 divisors (see below), whose sum is σ = 260275912704. Its totient is φ = 94421332800.

The previous prime is 168021208247. The next prime is 168021208273. The reversal of 168021208257 is 752802120861.

It is not a de Polignac number, because 168021208257 - 2⁴ = 168021208241 is a prime.

It is a super-2 number, since 2×168021208257² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (168021208207) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12022888 + ... + 12036854.

It is an arithmetic number, because the mean of its divisors is an integer number (8133622272).

Almost surely, 2^168021208257 is an apocalyptic number.

It is an amenable number.

168021208257 is a deficient number, since it is larger than the sum of its proper divisors (92254704447).

168021208257 is a wasteful number, since it uses less digits than its factorization.

168021208257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23429.

The product of its (nonzero) digits is 107520, while the sum is 42.

It can be divided in two parts, 168021 and 208257, that added together give a triangular number (376278 = T₈₆₇).

The spelling of 168021208257 in words is "one hundred sixty-eight billion, twenty-one million, two hundred eight thousand, two hundred fifty-seven".