31428761618 has 4 divisors (see below), whose sum is σ = 47143142430. Its totient is φ = 15714380808.

The previous prime is 31428761597. The next prime is 31428761633. The reversal of 31428761618 is 81616782413.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 18850466209 + 12578295409 = 137297^2 + 112153^2 .

It is a super-3 number, since 3×31428761618³ (a number of 32 digits) contains 333 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7857190403 + ... + 7857190406.

Almost surely, 2^31428761618 is an apocalyptic number.

31428761618 is a deficient number, since it is larger than the sum of its proper divisors (15714380812).

31428761618 is a wasteful number, since it uses less digits than its factorization.

31428761618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15714380811.

The product of its digits is 387072, while the sum is 47.

The spelling of 31428761618 in words is "thirty-one billion, four hundred twenty-eight million, seven hundred sixty-one thousand, six hundred eighteen".