18623787961 has 9 divisors (see below), whose sum is σ = 18734848293. Its totient is φ = 18513384540.

The previous prime is 18623787937. The next prime is 18623787967. The reversal of 18623787961 is 16978732681.

The square root of 18623787961 is 136469.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 18623787961 - 2⁹ = 18623787449 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18623787896 and 18623787905.

It is not an unprimeable number, because it can be changed into a prime (18623787967) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 32615806 + ... + 32616376.

Almost surely, 2^18623787961 is an apocalyptic number.

18623787961 is the 136469-th square number.

18623787961 is the 68235-th centered octagonal number.

It is an amenable number.

18623787961 is a deficient number, since it is larger than the sum of its proper divisors (111060332).

18623787961 is an frugal number, since it uses more digits than its factorization.

18623787961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1620 (or 810 counting only the distinct ones).

The product of its digits is 6096384, while the sum is 58.

The spelling of 18623787961 in words is "eighteen billion, six hundred twenty-three million, seven hundred eighty-seven thousand, nine hundred sixty-one".