1217822172 has 48 divisors (see below), whose sum is σ = 3359516160. Its totient is φ = 335950272.

The previous prime is 1217822171. The next prime is 1217822173. The reversal of 1217822172 is 2712287121.

It is an interprime number because it is at equal distance from previous prime (1217822171) and next prime (1217822173).

It is a super-2 number, since 2×1217822172² = 2966181685229595168, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1217822171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 247528 + ... + 252399.

It is an arithmetic number, because the mean of its divisors is an integer number (69989920).

Almost surely, 2^1217822172 is an apocalyptic number.

1217822172 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1217822172 is an abundant number, since it is smaller than the sum of its proper divisors (2141693988).

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

1217822172 is a wasteful number, since it uses less digits than its factorization.

1217822172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 499970 (or 499968 counting only the distinct ones).

The product of its digits is 6272, while the sum is 33.

The square root of 1217822172 is about 34897.3089506913. The cubic root of 1217822172 is about 1067.8935388837.

The spelling of 1217822172 in words is "one billion, two hundred seventeen million, eight hundred twenty-two thousand, one hundred seventy-two".