1817997172 has 24 divisors (see below), whose sum is σ = 3287747232. Its totient is φ = 879060000.

The previous prime is 1817997169. The next prime is 1817997173. The reversal of 1817997172 is 2717997181.

It is a super-2 number, since 2×1817997172² = 6610227434799995168, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1817997173) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34954 + ... + 69697.

It is an arithmetic number, because the mean of its divisors is an integer number (136989468).

Almost surely, 2^1817997172 is an apocalyptic number.

It is an amenable number.

1817997172 is a deficient number, since it is larger than the sum of its proper divisors (1469750060).

1817997172 is a wasteful number, since it uses less digits than its factorization.

1817997172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104799 (or 104797 counting only the distinct ones).

The product of its digits is 444528, while the sum is 52.

The square root of 1817997172 is about 42637.9780477452. The cubic root of 1817997172 is about 1220.4811261899.

Subtracting 1817997172 from its reverse (2717997181), we obtain a palindrome (900000009).

The spelling of 1817997172 in words is "one billion, eight hundred seventeen million, nine hundred ninety-seven thousand, one hundred seventy-two".