16691613461 has 2 divisors, whose sum is σ = 16691613462. Its totient is φ = 16691613460.

The previous prime is 16691613457. The next prime is 16691613481. The reversal of 16691613461 is 16431619661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14936506225 + 1755107236 = 122215^2 + 41894^2 .

It is an emirp because it is prime and its reverse (16431619661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16691613461 - 2² = 16691613457 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16691613431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8345806730 + 8345806731.

It is an arithmetic number, because the mean of its divisors is an integer number (8345806731).

Almost surely, 2^16691613461 is an apocalyptic number.

It is an amenable number.

16691613461 is a deficient number, since it is larger than the sum of its proper divisors (1).

16691613461 is an equidigital number, since it uses as much as digits as its factorization.

16691613461 is an evil number, because the sum of its binary digits is even.

The product of its digits is 139968, while the sum is 44.

The spelling of 16691613461 in words is "sixteen billion, six hundred ninety-one million, six hundred thirteen thousand, four hundred sixty-one".