19399680 has 132 divisors (see below), whose sum is σ = 67379052. Its totient is φ = 5160960.

The previous prime is 19399663. The next prime is 19399687. The reversal of 19399680 is 8699391.

It can be written as a sum of positive squares in 2 ways, for example, as 2359296 + 17040384 = 1536^2 + 4128^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (19399687) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 45870 + ... + 46290.

Almost surely, 2^19399680 is an apocalyptic number.

19399680 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 19399680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33689526).

19399680 is an abundant number, since it is smaller than the sum of its proper divisors (47979372).

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

19399680 is a wasteful number, since it uses less digits than its factorization.

19399680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 452 (or 431 counting only the distinct ones).

The product of its (nonzero) digits is 104976, while the sum is 45.

The square root of 19399680 is about 4404.5067828305. The cubic root of 19399680 is about 268.6982608169.

The spelling of 19399680 in words is "nineteen million, three hundred ninety-nine thousand, six hundred eighty".