17661849420 has 96 divisors (see below), whose sum is σ = 50513299200. Its totient is φ = 4609569024.

The previous prime is 17661849419. The next prime is 17661849421. The reversal of 17661849420 is 2494816671.

It is an interprime number because it is at equal distance from previous prime (17661849419) and next prime (17661849421).

It is a self number, because there is not a number n which added to its sum of digits gives 17661849420.

It is not an unprimeable number, because it can be changed into a prime (17661849421) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 799767 + ... + 821553.

It is an arithmetic number, because the mean of its divisors is an integer number (526180200).

Almost surely, 2^17661849420 is an apocalyptic number.

17661849420 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 17661849420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25256649600).

17661849420 is an abundant number, since it is smaller than the sum of its proper divisors (32851449780).

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

17661849420 is a wasteful number, since it uses less digits than its factorization.

17661849420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22087 (or 22085 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 48.

The spelling of 17661849420 in words is "seventeen billion, six hundred sixty-one million, eight hundred forty-nine thousand, four hundred twenty".