781320536 has 8 divisors (see below), whose sum is σ = 1464976020. Its totient is φ = 390660264.

The previous prime is 781320521. The next prime is 781320569. The reversal of 781320536 is 635023187.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×781320536² = 1220923559950654592, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 781320496 and 781320505.

It is a congruent number.

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 as a sum of consecutive naturals, namely, 48832526 + ... + 48832541.

Almost surely, 2^781320536 is an apocalyptic number.

It is an amenable number.

781320536 is a deficient number, since it is larger than the sum of its proper divisors (683655484).

781320536 is a wasteful number, since it uses less digits than its factorization.

781320536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97665073 (or 97665069 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 35.

The square root of 781320536 is about 27952.1114765951. Note that the first 3 decimals coincide. The cubic root of 781320536 is about 921.0355918895.

The spelling of 781320536 in words is "seven hundred eighty-one million, three hundred twenty thousand, five hundred thirty-six".