19785420 has 36 divisors (see below), whose sum is σ = 60016320. Its totient is φ = 5276064.

The previous prime is 19785419. The next prime is 19785427. The reversal of 19785420 is 2458791.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (19785427) 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, 54780 + ... + 55139.

It is an arithmetic number, because the mean of its divisors is an integer number (1667120).

Almost surely, 2^19785420 is an apocalyptic number.

19785420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19785420 is an abundant number, since it is smaller than the sum of its proper divisors (40230900).

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

19785420 is a wasteful number, since it uses less digits than its factorization.

19785420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109934 (or 109929 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 19785420 is about 4448.0804848833. The cubic root of 19785420 is about 270.4675028127.

The spelling of 19785420 in words is "nineteen million, seven hundred eighty-five thousand, four hundred twenty".