19851040 has 48 divisors (see below), whose sum is σ = 51166080. Its totient is φ = 7217920.

The previous prime is 19851037. The next prime is 19851071. The reversal of 19851040 is 4015891.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3880 + ... + 7399.

It is an arithmetic number, because the mean of its divisors is an integer number (1065960).

Almost surely, 2^19851040 is an apocalyptic number.

19851040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19851040 is an abundant number, since it is smaller than the sum of its proper divisors (31315040).

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

19851040 is a wasteful number, since it uses less digits than its factorization.

19851040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11305 (or 11297 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 28.

The square root of 19851040 is about 4455.4505944966. The cubic root of 19851040 is about 270.7661822209.

It can be divided in two parts, 1985 and 1040, that added together give a square (3025 = 55²).

The spelling of 19851040 in words is "nineteen million, eight hundred fifty-one thousand, forty".