1616494661 has 2 divisors, whose sum is σ = 1616494662. Its totient is φ = 1616494660.

The previous prime is 1616494651. The next prime is 1616494667. The reversal of 1616494661 is 1664946161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1273133761 + 343360900 = 35681^2 + 18530^2 .

It is an emirp because it is prime and its reverse (1664946161) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1616494661 - 2¹⁴ = 1616478277 is a prime.

It is a super-2 number, since 2×1616494661² = 5226109978083009842, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1616494667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 808247330 + 808247331.

It is an arithmetic number, because the mean of its divisors is an integer number (808247331).

Almost surely, 2^1616494661 is an apocalyptic number.

It is an amenable number.

1616494661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1616494661 is an equidigital number, since it uses as much as digits as its factorization.

1616494661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 186624, while the sum is 44.

The square root of 1616494661 is about 40205.6545898708. The cubic root of 1616494661 is about 1173.6125856847.

The spelling of 1616494661 in words is "one billion, six hundred sixteen million, four hundred ninety-four thousand, six hundred sixty-one".