781421400 has 144 divisors (see below), whose sum is σ = 2674114560. Its totient is φ = 204422400.

The previous prime is 781421393. The next prime is 781421401. The reversal of 781421400 is 4124187.

781421400 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×781421400² = 1221238808755920000, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (781421401) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 91305 + ... + 99495.

It is an arithmetic number, because the mean of its divisors is an integer number (18570240).

Almost surely, 2^781421400 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 781421400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1337057280).

781421400 is an abundant number, since it is smaller than the sum of its proper divisors (1892693160).

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

781421400 is a wasteful number, since it uses less digits than its factorization.

781421400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8266 (or 8254 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The square root of 781421400 is about 27953.9156470073. The cubic root of 781421400 is about 921.0752236549.

Adding to 781421400 its reverse (4124187), we get a palindrome (785545587).

The spelling of 781421400 in words is "seven hundred eighty-one million, four hundred twenty-one thousand, four hundred".