19959540 has 48 divisors (see below), whose sum is σ = 57818880. Its totient is φ = 5138560.

The previous prime is 19959517. The next prime is 19959559. The reversal of 19959540 is 4595991.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 19959492 and 19959501.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3996 + ... + 7475.

It is an arithmetic number, because the mean of its divisors is an integer number (1204560).

Almost surely, 2^19959540 is an apocalyptic number.

19959540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19959540 is an abundant number, since it is smaller than the sum of its proper divisors (37859340).

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

19959540 is a wasteful number, since it uses less digits than its factorization.

19959540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11512 (or 11510 counting only the distinct ones).

The product of its (nonzero) digits is 72900, while the sum is 42.

The square root of 19959540 is about 4467.6100993708. The cubic root of 19959540 is about 271.2585958612.

The spelling of 19959540 in words is "nineteen million, nine hundred fifty-nine thousand, five hundred forty".