19961600 has 54 divisors (see below), whose sum is σ = 49423920. Its totient is φ = 7982080.

The previous prime is 19961593. The next prime is 19961603. The reversal of 19961600 is 616991.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19961603) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4841 + ... + 7959.

Almost surely, 2^19961600 is an apocalyptic number.

19961600 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 19961600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24711960).

19961600 is an abundant number, since it is smaller than the sum of its proper divisors (29462320).

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

19961600 is an equidigital number, since it uses as much as digits as its factorization.

19961600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3145 (or 3126 counting only the distinct ones).

The product of its (nonzero) digits is 2916, while the sum is 32.

The square root of 19961600 is about 4467.8406417418. The cubic root of 19961600 is about 271.2679276307.

The spelling of 19961600 in words is "nineteen million, nine hundred sixty-one thousand, six hundred".