17972081 has 4 divisors (see below), whose sum is σ = 18918000. Its totient is φ = 17026164.

The previous prime is 17972023. The next prime is 17972099. The reversal of 17972081 is 18027971.

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, and also an emirpimes, since its reverse is a distinct semiprime: 18027971 = 13 ⋅1386767.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-17972081 is a prime.

It is a super-2 number, since 2×17972081² = 645991390941122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (17972681) 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, 472931 + ... + 472968.

It is an arithmetic number, because the mean of its divisors is an integer number (4729500).

Almost surely, 2^17972081 is an apocalyptic number.

It is an amenable number.

17972081 is a deficient number, since it is larger than the sum of its proper divisors (945919).

17972081 is an equidigital number, since it uses as much as digits as its factorization.

17972081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 945918.

The product of its (nonzero) digits is 7056, while the sum is 35.

The square root of 17972081 is about 4239.3491245709. The cubic root of 17972081 is about 261.9385721226.

The spelling of 17972081 in words is "seventeen million, nine hundred seventy-two thousand, eighty-one".