18220534 has 4 divisors (see below), whose sum is σ = 27330804. Its totient is φ = 9110266.

The previous prime is 18220513. The next prime is 18220561. The reversal of 18220534 is 43502281.

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

It is a junction number, because it is equal to n+sod(n) for n = 18220499 and 18220508.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4555132 + ... + 4555135.

It is an arithmetic number, because the mean of its divisors is an integer number (6832701).

Almost surely, 2^18220534 is an apocalyptic number.

18220534 is a deficient number, since it is larger than the sum of its proper divisors (9110270).

18220534 is an equidigital number, since it uses as much as digits as its factorization.

18220534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9110269.

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 18220534 is about 4268.5517450302. The cubic root of 18220534 is about 263.1400989412.

The spelling of 18220534 in words is "eighteen million, two hundred twenty thousand, five hundred thirty-four".