781329972 has 12 divisors (see below), whose sum is σ = 1823103296. Its totient is φ = 260443320.

The previous prime is 781329961. The next prime is 781329973. The reversal of 781329972 is 279923187.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×781329972² = 1220953050291041568, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (781329973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32555404 + ... + 32555427.

Almost surely, 2^781329972 is an apocalyptic number.

It is an amenable number.

781329972 is an abundant number, since it is smaller than the sum of its proper divisors (1041773324).

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

781329972 is a wasteful number, since it uses less digits than its factorization.

781329972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65110838 (or 65110836 counting only the distinct ones).

The product of its digits is 381024, while the sum is 48.

The square root of 781329972 is about 27952.2802647655. The cubic root of 781329972 is about 921.0392996537.

The spelling of 781329972 in words is "seven hundred eighty-one million, three hundred twenty-nine thousand, nine hundred seventy-two".