820781798 has 16 divisors (see below), whose sum is σ = 1296752640. Its totient is φ = 388557000.

The previous prime is 820781737. The next prime is 820781813. The reversal of 820781798 is 897187028.

It is a happy number.

It is a super-2 number, since 2×820781798² = 1347365519856225608, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 68603 + ... + 79673.

It is an arithmetic number, because the mean of its divisors is an integer number (81047040).

Almost surely, 2^820781798 is an apocalyptic number.

820781798 is a deficient number, since it is larger than the sum of its proper divisors (475970842).

820781798 is a wasteful number, since it uses less digits than its factorization.

820781798 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13043.

The product of its (nonzero) digits is 451584, while the sum is 50.

The square root of 820781798 is about 28649.2896596059. The cubic root of 820781798 is about 936.2875293081.

The spelling of 820781798 in words is "eight hundred twenty million, seven hundred eighty-one thousand, seven hundred ninety-eight".