18906513 has 4 divisors (see below), whose sum is σ = 25208688. Its totient is φ = 12604340.

The previous prime is 18906509. The next prime is 18906551. The reversal of 18906513 is 31560981.

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 18906513 - 2² = 18906509 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18906553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3151083 + ... + 3151088.

It is an arithmetic number, because the mean of its divisors is an integer number (6302172).

Almost surely, 2^18906513 is an apocalyptic number.

It is an amenable number.

18906513 is a deficient number, since it is larger than the sum of its proper divisors (6302175).

18906513 is an equidigital number, since it uses as much as digits as its factorization.

18906513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6302174.

The product of its (nonzero) digits is 6480, while the sum is 33.

The square root of 18906513 is about 4348.1620255000. The cubic root of 18906513 is about 266.4017944626.

It can be divided in two parts, 18 and 906513, that added together give a triangular number (906531 = T₁₃₄₆).

The spelling of 18906513 in words is "eighteen million, nine hundred six thousand, five hundred thirteen".