781361648 has 20 divisors (see below), whose sum is σ = 1515689448. Its totient is φ = 390216000.

The previous prime is 781361639. The next prime is 781361653. The reversal of 781361648 is 846163187.

It is a super-2 number, since 2×781361648² = 1221052049930551808, which contains 22 as substring.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 781361599 and 781361608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14978 + ... + 42273.

Almost surely, 2^781361648 is an apocalyptic number.

It is an amenable number.

781361648 is a deficient number, since it is larger than the sum of its proper divisors (734327800).

781361648 is a wasteful number, since it uses less digits than its factorization.

781361648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58112 (or 58106 counting only the distinct ones).

The product of its digits is 193536, while the sum is 44.

The square root of 781361648 is about 27952.8468675375. The cubic root of 781361648 is about 921.0517461435.

The spelling of 781361648 in words is "seven hundred eighty-one million, three hundred sixty-one thousand, six hundred forty-eight".