781074432 has 90 divisors (see below), whose sum is σ = 2256794358. Its totient is φ = 260308992.

The previous prime is 781074407. The next prime is 781074443. The reversal of 781074432 is 234470187.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 743325696 + 37748736 = 27264^2 + 6144^2 .

It is a super-2 number, since 2×781074432² = 1220154536648245248, 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 polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 144808 + ... + 150104.

Almost surely, 2^781074432 is an apocalyptic number.

781074432 is a gapful number since it is divisible by the number (72) 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 781074432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1128397179).

781074432 is an abundant number, since it is smaller than the sum of its proper divisors (1475719926).

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

781074432 is an equidigital number, since it uses as much as digits as its factorization.

781074432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5331 (or 5302 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 36.

The square root of 781074432 is about 27947.7088864186. The cubic root of 781074432 is about 920.9388777002.

The spelling of 781074432 in words is "seven hundred eighty-one million, seventy-four thousand, four hundred thirty-two".