19778850 has 288 divisors, whose sum is σ = 71245440. Its totient is φ = 3991680.

The previous prime is 19778849. The next prime is 19778861. The reversal of 19778850 is 5887791.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a junction number, because it is equal to n+sod(n) for n = 19778796 and 19778805.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 859939 + ... + 859961.

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

Almost surely, 2^19778850 is an apocalyptic number.

19778850 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 19778850, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35622720).

19778850 is an abundant number, since it is smaller than the sum of its proper divisors (51466590).

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

19778850 is a wasteful number, since it uses less digits than its factorization.

19778850 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71 (or 53 counting only the distinct ones).

The product of its (nonzero) digits is 141120, while the sum is 45.

The square root of 19778850 is about 4447.3419027549. The cubic root of 19778850 is about 270.4375621085.

The spelling of 19778850 in words is "nineteen million, seven hundred seventy-eight thousand, eight hundred fifty".