163970521 has 16 divisors (see below), whose sum is σ = 197342208. Its totient is φ = 134236800.

The previous prime is 163970503. The next prime is 163970531. The reversal of 163970521 is 125079361.

It is a cyclic number.

It is not a de Polignac number, because 163970521 - 2⁵ = 163970489 is a prime.

It is a super-2 number, since 2×163970521² = 53772663514022882, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (163970531) 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, 8121 + ... + 19846.

It is an arithmetic number, because the mean of its divisors is an integer number (12333888).

Almost surely, 2^163970521 is an apocalyptic number.

163970521 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

163970521 is a deficient number, since it is larger than the sum of its proper divisors (33371687).

163970521 is a wasteful number, since it uses less digits than its factorization.

163970521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28032.

The product of its (nonzero) digits is 11340, while the sum is 34.

The square root of 163970521 is about 12805.0974615580. The cubic root of 163970521 is about 547.3375689067.

The spelling of 163970521 in words is "one hundred sixty-three million, nine hundred seventy thousand, five hundred twenty-one".