16621432231 has 2 divisors, whose sum is σ = 16621432232. Its totient is φ = 16621432230.

The previous prime is 16621432193. The next prime is 16621432249. The reversal of 16621432231 is 13223412661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 16621432231 - 2²⁵ = 16587877799 is a prime.

It is a super-2 number, since 2×16621432231² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 16621432193 and 16621432202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16621432031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8310716115 + 8310716116.

It is an arithmetic number, because the mean of its divisors is an integer number (8310716116).

Almost surely, 2^16621432231 is an apocalyptic number.

16621432231 is a deficient number, since it is larger than the sum of its proper divisors (1).

16621432231 is an equidigital number, since it uses as much as digits as its factorization.

16621432231 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10368, while the sum is 31.

Adding to 16621432231 its reverse (13223412661), we get a palindrome (29844844892).

The spelling of 16621432231 in words is "sixteen billion, six hundred twenty-one million, four hundred thirty-two thousand, two hundred thirty-one".