2018631391 has 24 divisors (see below), whose sum is σ = 2572099920. Its totient is φ = 1572302592.

The previous prime is 2018631379. The next prime is 2018631397. The reversal of 2018631391 is 1931368102.

It is not a de Polignac number, because 2018631391 - 2¹³ = 2018623199 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2018631397) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17625 + ... + 65938.

It is an arithmetic number, because the mean of its divisors is an integer number (107170830).

Almost surely, 2^2018631391 is an apocalyptic number.

2018631391 is a deficient number, since it is larger than the sum of its proper divisors (553468529).

2018631391 is a wasteful number, since it uses less digits than its factorization.

2018631391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83623 (or 83616 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 2018631391 is about 44929.1819533808. The cubic root of 2018631391 is about 1263.8213105888.

Adding to 2018631391 its reverse (1931368102), we get a palindrome (3949999493).

The spelling of 2018631391 in words is "two billion, eighteen million, six hundred thirty-one thousand, three hundred ninety-one".