18022793978 has 12 divisors (see below), whose sum is σ = 31447936602. Its totient is φ = 7724054520.

The previous prime is 18022793977. The next prime is 18022794011. The reversal of 18022793978 is 87939722081.

It can be written as a sum of positive squares in only one way, i.e., 13468298809 + 4554495169 = 116053^2 + 67487^2 .

It is a super-2 number, since 2×18022793978² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18022793977) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 91952933 + ... + 91953128.

Almost surely, 2^18022793978 is an apocalyptic number.

18022793978 is a deficient number, since it is larger than the sum of its proper divisors (13425142624).

18022793978 is a wasteful number, since it uses less digits than its factorization.

18022793978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 183906077 (or 183906070 counting only the distinct ones).

The product of its (nonzero) digits is 3048192, while the sum is 56.

The spelling of 18022793978 in words is "eighteen billion, twenty-two million, seven hundred ninety-three thousand, nine hundred seventy-eight".