1623123661 has 2 divisors, whose sum is σ = 1623123662. Its totient is φ = 1623123660.

The previous prime is 1623123653. The next prime is 1623123737. The reversal of 1623123661 is 1663213261.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1434061161 + 189062500 = 37869^2 + 13750^2 .

It is a cyclic number.

It is not a de Polignac number, because 1623123661 - 2³ = 1623123653 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1623123611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 811561830 + 811561831.

It is an arithmetic number, because the mean of its divisors is an integer number (811561831).

Almost surely, 2^1623123661 is an apocalyptic number.

It is an amenable number.

1623123661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1623123661 is an equidigital number, since it uses as much as digits as its factorization.

1623123661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7776, while the sum is 31.

The square root of 1623123661 is about 40288.0088984303. The cubic root of 1623123661 is about 1175.2146669205.

The spelling of 1623123661 in words is "one billion, six hundred twenty-three million, one hundred twenty-three thousand, six hundred sixty-one".