781656490 has 8 divisors (see below), whose sum is σ = 1406981700. Its totient is φ = 312662592.

The previous prime is 781656461. The next prime is 781656497. The reversal of 781656490 is 94656187.

781656490 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 767345401 + 14311089 = 27701^2 + 3783^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×781656490² = 1221973736718240200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 781656490.

It is not an unprimeable number, because it can be changed into a prime (781656497) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39082815 + ... + 39082834.

Almost surely, 2^781656490 is an apocalyptic number.

781656490 is a deficient number, since it is larger than the sum of its proper divisors (625325210).

781656490 is a wasteful number, since it uses less digits than its factorization.

781656490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78165656.

The product of its (nonzero) digits is 362880, while the sum is 46.

The square root of 781656490 is about 27958.1202873155. The cubic root of 781656490 is about 921.1675826404.

The spelling of 781656490 in words is "seven hundred eighty-one million, six hundred fifty-six thousand, four hundred ninety".