2172997818 has 24 divisors (see below), whose sum is σ = 4912865568. Its totient is φ = 692839752.

The previous prime is 2172997807. The next prime is 2172997829. The reversal of 2172997818 is 8187992712.

It is an interprime number because it is at equal distance from previous prime (2172997807) and next prime (2172997829).

It is a super-2 number, since 2×2172997818² = 9443839034065522248, which contains 22 as substring.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2623980 + ... + 2624807.

It is an arithmetic number, because the mean of its divisors is an integer number (204702732).

Almost surely, 2^2172997818 is an apocalyptic number.

2172997818 is an abundant number, since it is smaller than the sum of its proper divisors (2739867750).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2172997818 is a wasteful number, since it uses less digits than its factorization.

2172997818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5248818 (or 5248815 counting only the distinct ones).

The product of its digits is 1016064, while the sum is 54.

The square root of 2172997818 is about 46615.4246789622. The cubic root of 2172997818 is about 1295.2484962129.

The spelling of 2172997818 in words is "two billion, one hundred seventy-two million, nine hundred ninety-seven thousand, eight hundred eighteen".