19740240 has 320 divisors, whose sum is σ = 79161600. Its totient is φ = 4478976.

The previous prime is 19740239. The next prime is 19740241. The reversal of 19740240 is 4204791.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (19740239) and next prime (19740241).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19740241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 533502 + ... + 533538.

It is an arithmetic number, because the mean of its divisors is an integer number (247380).

Almost surely, 2^19740240 is an apocalyptic number.

19740240 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 19740240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39580800).

19740240 is an abundant number, since it is smaller than the sum of its proper divisors (59421360).

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

19740240 is a wasteful number, since it uses less digits than its factorization.

19740240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91 (or 79 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 19740240 is about 4442.9989871707. The cubic root of 19740240 is about 270.2614750940.

The spelling of 19740240 in words is "nineteen million, seven hundred forty thousand, two hundred forty".