123415661 has 2 divisors, whose sum is σ = 123415662. Its totient is φ = 123415660.

The previous prime is 123415651. The next prime is 123415709. The reversal of 123415661 is 166514321.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 73444900 + 49970761 = 8570^2 + 7069^2 .

It is a cyclic number.

It is not a de Polignac number, because 123415661 - 2¹⁰ = 123414637 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (123415651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61707830 + 61707831.

It is an arithmetic number, because the mean of its divisors is an integer number (61707831).

Almost surely, 2^123415661 is an apocalyptic number.

It is an amenable number.

123415661 is a deficient number, since it is larger than the sum of its proper divisors (1).

123415661 is an equidigital number, since it uses as much as digits as its factorization.

123415661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4320, while the sum is 29.

The square root of 123415661 is about 11109.2601463824. The cubic root of 123415661 is about 497.8785597123.

Adding to 123415661 its reverse (166514321), we get a palindrome (289929982).

The spelling of 123415661 in words is "one hundred twenty-three million, four hundred fifteen thousand, six hundred sixty-one".