18156047 has 16 divisors (see below), whose sum is σ = 22536192. Its totient is φ = 14243040.

The previous prime is 18156043. The next prime is 18156067. The reversal of 18156047 is 74065181.

It is a happy number.

It is not a de Polignac number, because 18156047 - 2² = 18156043 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18156043) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10772 + ... + 12342.

It is an arithmetic number, because the mean of its divisors is an integer number (1408512).

Almost surely, 2^18156047 is an apocalyptic number.

18156047 is a deficient number, since it is larger than the sum of its proper divisors (4380145).

18156047 is a wasteful number, since it uses less digits than its factorization.

18156047 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1718.

The product of its (nonzero) digits is 6720, while the sum is 32.

The square root of 18156047 is about 4260.9913165835. The cubic root of 18156047 is about 262.8292925670.

The spelling of 18156047 in words is "eighteen million, one hundred fifty-six thousand, forty-seven".