18945891433 has 16 divisors (see below), whose sum is σ = 22511631744. Its totient is φ = 15606771840.

The previous prime is 18945891427. The next prime is 18945891449. The reversal of 18945891433 is 33419854981.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 18945891433 - 2⁹ = 18945890921 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18945891463) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 473410 + ... + 511867.

It is an arithmetic number, because the mean of its divisors is an integer number (1406976984).

Almost surely, 2^18945891433 is an apocalyptic number.

It is an amenable number.

18945891433 is a deficient number, since it is larger than the sum of its proper divisors (3565740311).

18945891433 is an equidigital number, since it uses as much as digits as its factorization.

18945891433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 985392.

The product of its digits is 3732480, while the sum is 55.

The spelling of 18945891433 in words is "eighteen billion, nine hundred forty-five million, eight hundred ninety-one thousand, four hundred thirty-three".