19707940 has 96 divisors (see below), whose sum is σ = 51609600. Its totient is φ = 6168960.

The previous prime is 19707931. The next prime is 19707943. The reversal of 19707940 is 4970791.

It is a self number, because there is not a number n which added to its sum of digits gives 19707940.

It is not an unprimeable number, because it can be changed into a prime (19707943) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 82341 + ... + 82579.

It is an arithmetic number, because the mean of its divisors is an integer number (537600).

Almost surely, 2^19707940 is an apocalyptic number.

19707940 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 19707940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25804800).

19707940 is an abundant number, since it is smaller than the sum of its proper divisors (31901660).

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

19707940 is a wasteful number, since it uses less digits than its factorization.

19707940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 305 (or 303 counting only the distinct ones).

The product of its (nonzero) digits is 15876, while the sum is 37.

The square root of 19707940 is about 4439.3625668557. The cubic root of 19707940 is about 270.1139893632.

The spelling of 19707940 in words is "nineteen million, seven hundred seven thousand, nine hundred forty".