19992840 has 64 divisors (see below), whose sum is σ = 68549760. Its totient is φ = 4569600.

The previous prime is 19992829. The next prime is 19992877. The reversal of 19992840 is 4829991.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 19992792 and 19992801.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11061 + ... + 12740.

It is an arithmetic number, because the mean of its divisors is an integer number (1071090).

Almost surely, 2^19992840 is an apocalyptic number.

19992840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19992840 is an abundant number, since it is smaller than the sum of its proper divisors (48556920).

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

19992840 is a wasteful number, since it uses less digits than its factorization.

19992840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23822 (or 23818 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 42.

The square root of 19992840 is about 4471.3353710050. The cubic root of 19992840 is about 271.4093657430.

It can be divided in two parts, 199 and 92840, that added together give a palindrome (93039).

The spelling of 19992840 in words is "nineteen million, nine hundred ninety-two thousand, eight hundred forty".