781738020 has 192 divisors, whose sum is σ = 2818583040. Its totient is φ = 176173056.

The previous prime is 781737973. The next prime is 781738039. The reversal of 781738020 is 20837187.

It is a super-2 number, since 2×781738020² = 1222228663827040800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 274524 + ... + 277356.

It is an arithmetic number, because the mean of its divisors is an integer number (14680120).

Almost surely, 2^781738020 is an apocalyptic number.

781738020 is a gapful number since it is divisible by the number (70) 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 781738020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1409291520).

781738020 is an abundant number, since it is smaller than the sum of its proper divisors (2036845020).

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

781738020 is a wasteful number, since it uses less digits than its factorization.

781738020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2931 (or 2923 counting only the distinct ones).

The product of its (nonzero) digits is 18816, while the sum is 36.

The square root of 781738020 is about 27959.5783230005. The cubic root of 781738020 is about 921.1996087213.

The spelling of 781738020 in words is "seven hundred eighty-one million, seven hundred thirty-eight thousand, twenty".