780533681 has 6 divisors (see below), whose sum is σ = 815945970. Its totient is φ = 746596928.

The previous prime is 780533671. The next prime is 780533713. The reversal of 780533681 is 186335087.

It can be written as a sum of positive squares in only one way, i.e., 730350625 + 50183056 = 27025^2 + 7084^2 .

It is not a de Polignac number, because 780533681 - 2¹⁰ = 780532657 is a prime.

It is a super-2 number, since 2×780533681² = 1218465654350819522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (780533641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 737216 + ... + 738273.

It is an arithmetic number, because the mean of its divisors is an integer number (135990995).

Almost surely, 2^780533681 is an apocalyptic number.

It is an amenable number.

780533681 is a deficient number, since it is larger than the sum of its proper divisors (35412289).

780533681 is a wasteful number, since it uses less digits than its factorization.

780533681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1475535 (or 1475512 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 41.

The square root of 780533681 is about 27938.0328763498. The cubic root of 780533681 is about 920.7263014645.

The spelling of 780533681 in words is "seven hundred eighty million, five hundred thirty-three thousand, six hundred eighty-one".