781672 has 16 divisors (see below), whose sum is σ = 1476000. Its totient is φ = 388080.

The previous prime is 781661. The next prime is 781673. The reversal of 781672 is 276187.

It is a happy number.

It is a super-2 number, since 2×781672² = 1222022231168, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (781673) by changing a digit.

781672 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1347 + ... + 1837.

It is an arithmetic number, because the mean of its divisors is an integer number (92250).

2⁷⁸¹⁶⁷² is an apocalyptic number.

It is an amenable number.

781672 is a deficient number, since it is larger than the sum of its proper divisors (694328).

781672 is a wasteful number, since it uses less digits than its factorization.

781672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 696 (or 692 counting only the distinct ones).

The product of its digits is 4704, while the sum is 31.

The square root of 781672 is about 884.1221635046. The cubic root of 781672 is about 92.1173675349.

The spelling of 781672 in words is "seven hundred eighty-one thousand, six hundred seventy-two".