18272731 has 2 divisors, whose sum is σ = 18272732. Its totient is φ = 18272730.

The previous prime is 18272701. The next prime is 18272747. The reversal of 18272731 is 13727281.

It is a strong prime.

It is an emirp because it is prime and its reverse (13727281) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18272731 - 2¹³ = 18264539 is a prime.

It is a super-2 number, since 2×18272731² = 667785396396722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 18272693 and 18272702.

It is not a weakly prime, because it can be changed into another prime (18272701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9136365 + 9136366.

It is an arithmetic number, because the mean of its divisors is an integer number (9136366).

Almost surely, 2^18272731 is an apocalyptic number.

18272731 is a deficient number, since it is larger than the sum of its proper divisors (1).

18272731 is an equidigital number, since it uses as much as digits as its factorization.

18272731 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4704, while the sum is 31.

The square root of 18272731 is about 4274.6615070670. The cubic root of 18272731 is about 263.3911349198.

The spelling of 18272731 in words is "eighteen million, two hundred seventy-two thousand, seven hundred thirty-one".