18656021073 has 32 divisors (see below), whose sum is σ = 26535444480. Its totient is φ = 11633240960.

The previous prime is 18656021063. The next prime is 18656021077. The reversal of 18656021073 is 37012065681.

It is a cyclic number.

It is not a de Polignac number, because 18656021073 - 2⁴ = 18656021057 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18656021077) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 765565 + ... + 789557.

It is an arithmetic number, because the mean of its divisors is an integer number (829232640).

Almost surely, 2^18656021073 is an apocalyptic number.

It is an amenable number.

18656021073 is a deficient number, since it is larger than the sum of its proper divisors (7879423407).

18656021073 is a wasteful number, since it uses less digits than its factorization.

18656021073 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24269.

The product of its (nonzero) digits is 60480, while the sum is 39.

The spelling of 18656021073 in words is "eighteen billion, six hundred fifty-six million, twenty-one thousand, seventy-three".