16661337431 has 2 divisors, whose sum is σ = 16661337432. Its totient is φ = 16661337430.

The previous prime is 16661337401. The next prime is 16661337439. The reversal of 16661337431 is 13473316661.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 16661337431 - 2³⁰ = 15587595607 is a prime.

It is a super-2 number, since 2×16661337431² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16661337439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8330668715 + 8330668716.

It is an arithmetic number, because the mean of its divisors is an integer number (8330668716).

Almost surely, 2^16661337431 is an apocalyptic number.

16661337431 is a deficient number, since it is larger than the sum of its proper divisors (1).

16661337431 is an equidigital number, since it uses as much as digits as its factorization.

16661337431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 163296, while the sum is 41.

The spelling of 16661337431 in words is "sixteen billion, six hundred sixty-one million, three hundred thirty-seven thousand, four hundred thirty-one".