19858040 has 128 divisors (see below), whose sum is σ = 52488000. Its totient is φ = 6709248.

The previous prime is 19858037. The next prime is 19858049. The reversal of 19858040 is 4085891.

19858040 = T₂₄₇ + T₂₄₈ + ... + T₅₁₁.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19858049) 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 31 ways as a sum of consecutive naturals, for example, 374654 + ... + 374706.

Almost surely, 2^19858040 is an apocalyptic number.

19858040 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 19858040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26244000).

19858040 is an abundant number, since it is smaller than the sum of its proper divisors (32629960).

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

19858040 is a wasteful number, since it uses less digits than its factorization.

19858040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129 (or 125 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 35.

The square root of 19858040 is about 4456.2360799222. The cubic root of 19858040 is about 270.7980049119.

The spelling of 19858040 in words is "nineteen million, eight hundred fifty-eight thousand, forty".