1918120513 has 4 divisors (see below), whose sum is σ = 1924898608. Its totient is φ = 1911342420.

The previous prime is 1918120511. The next prime is 1918120517. The reversal of 1918120513 is 3150218191.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1918120513 - 2¹ = 1918120511 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1918120511) 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, 3388623 + ... + 3389188.

It is an arithmetic number, because the mean of its divisors is an integer number (481224652).

Almost surely, 2^1918120513 is an apocalyptic number.

It is an amenable number.

1918120513 is a deficient number, since it is larger than the sum of its proper divisors (6778095).

1918120513 is an equidigital number, since it uses as much as digits as its factorization.

1918120513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6778094.

The product of its (nonzero) digits is 2160, while the sum is 31.

The square root of 1918120513 is about 43796.3527362725. The cubic root of 1918120513 is about 1242.4873142059.

The spelling of 1918120513 in words is "one billion, nine hundred eighteen million, one hundred twenty thousand, five hundred thirteen".