17972820 has 96 divisors (see below), whose sum is σ = 56730240. Its totient is φ = 4723200.

The previous prime is 17972813. The next prime is 17972833. The reversal of 17972820 is 2827971.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 44620 + ... + 45020.

It is an arithmetic number, because the mean of its divisors is an integer number (590940).

Almost surely, 2^17972820 is an apocalyptic number.

17972820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 17972820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28365120).

17972820 is an abundant number, since it is smaller than the sum of its proper divisors (38757420).

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

17972820 is a wasteful number, since it uses less digits than its factorization.

17972820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 502 (or 494 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 36.

The square root of 17972820 is about 4239.4362832811. The cubic root of 17972820 is about 261.9421623199.

The spelling of 17972820 in words is "seventeen million, nine hundred seventy-two thousand, eight hundred twenty".