19424640 has 128 divisors (see below), whose sum is σ = 63256320. Its totient is φ = 5068800.

The previous prime is 19424633. The next prime is 19424641. The reversal of 19424640 is 4642491.

It is a tau number, because it is divible by the number of its divisors (128).

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 19424598 and 19424607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19424641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 128565 + ... + 128715.

It is an arithmetic number, because the mean of its divisors is an integer number (494190).

Almost surely, 2^19424640 is an apocalyptic number.

19424640 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 19424640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31628160).

19424640 is an abundant number, since it is smaller than the sum of its proper divisors (43831680).

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

19424640 is a wasteful number, since it uses less digits than its factorization.

19424640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240 (or 228 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 19424640 is about 4407.3393334301. The cubic root of 19424640 is about 268.8134488736.

The spelling of 19424640 in words is "nineteen million, four hundred twenty-four thousand, six hundred forty".