163506532425221 has 4 divisors (see below), whose sum is σ = 163508783940672. Its totient is φ = 163504280909772.

The previous prime is 163506532425143. The next prime is 163506532425281. The reversal of 163506532425221 is 122524235605361.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 163506532425221 - 2³⁰ = 163505458683397 is a prime.

It is a super-2 number, since 2×163506532425221² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (163506532425281) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1125648791 + ... + 1125794036.

It is an arithmetic number, because the mean of its divisors is an integer number (40877195985168).

Almost surely, 2^{163506532425221} is an apocalyptic number.

It is an amenable number.

163506532425221 is a deficient number, since it is larger than the sum of its proper divisors (2251515451).

163506532425221 is an equidigital number, since it uses as much as digits as its factorization.

163506532425221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2251515450.

The product of its (nonzero) digits is 2592000, while the sum is 47.

The spelling of 163506532425221 in words is "one hundred sixty-three trillion, five hundred six billion, five hundred thirty-two million, four hundred twenty-five thousand, two hundred twenty-one".