390677781 has 16 divisors (see below), whose sum is σ = 565397504. Its totient is φ = 238521024.

The previous prime is 390677767. The next prime is 390677803. The reversal of 390677781 is 187776093.

It is a happy number.

It is not a de Polignac number, because 390677781 - 2⁷ = 390677653 is a prime.

It is a super-2 number, since 2×390677781² = 305258257134167922, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 390677781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (390677711) 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 15 ways as a sum of consecutive naturals, for example, 34486 + ... + 44391.

It is an arithmetic number, because the mean of its divisors is an integer number (35337344).

Almost surely, 2^390677781 is an apocalyptic number.

It is an amenable number.

390677781 is a deficient number, since it is larger than the sum of its proper divisors (174719723).

390677781 is a wasteful number, since it uses less digits than its factorization.

390677781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79020.

The product of its (nonzero) digits is 444528, while the sum is 48.

The square root of 390677781 is about 19765.5705963678. The cubic root of 390677781 is about 731.0373573542.

The spelling of 390677781 in words is "three hundred ninety million, six hundred seventy-seven thousand, seven hundred eighty-one".