18196331653 has 4 divisors (see below), whose sum is σ = 18258435468. Its totient is φ = 18134227840.

The previous prime is 18196331603. The next prime is 18196331669. The reversal of 18196331653 is 35613369181.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 35613369181 = 13 ⋅2739489937.

It can be written as a sum of positive squares in 2 ways, for example, as 8915514084 + 9280817569 = 94422^2 + 96337^2 .

It is a cyclic number.

It is not a de Polignac number, because 18196331653 - 2²¹ = 18194234501 is a prime.

It is a super-2 number, since 2×18196331653² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18196331603) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31051468 + ... + 31052053.

It is an arithmetic number, because the mean of its divisors is an integer number (4564608867).

Almost surely, 2^18196331653 is an apocalyptic number.

It is an amenable number.

18196331653 is a deficient number, since it is larger than the sum of its proper divisors (62103815).

18196331653 is an equidigital number, since it uses as much as digits as its factorization.

18196331653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62103814.

The product of its digits is 349920, while the sum is 46.

The spelling of 18196331653 in words is "eighteen billion, one hundred ninety-six million, three hundred thirty-one thousand, six hundred fifty-three".