17981964 has 144 divisors (see below), whose sum is σ = 61152000. Its totient is φ = 4302720.

The previous prime is 17981959. The next prime is 17981969. The reversal of 17981964 is 46918971.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (17981959) and next prime (17981969).

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (17981969) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 35787 + ... + 36285.

Almost surely, 2^17981964 is an apocalyptic number.

17981964 is a gapful number since it is divisible by the number (14) 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 17981964, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30576000).

17981964 is an abundant number, since it is smaller than the sum of its proper divisors (43170036).

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

17981964 is a wasteful number, since it uses less digits than its factorization.

17981964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 540 (or 535 counting only the distinct ones).

The product of its digits is 108864, while the sum is 45.

The square root of 17981964 is about 4240.5145914146. The cubic root of 17981964 is about 261.9865774061.

The spelling of 17981964 in words is "seventeen million, nine hundred eighty-one thousand, nine hundred sixty-four".