821366436 has 24 divisors (see below), whose sum is σ = 2090751264. Its totient is φ = 248898880.

The previous prime is 821366431. The next prime is 821366443. The reversal of 821366436 is 634663128.

It is a junction number, because it is equal to n+sod(n) for n = 821366394 and 821366403.

It is not an unprimeable number, because it can be changed into a prime (821366431) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3111105 + ... + 3111368.

It is an arithmetic number, because the mean of its divisors is an integer number (87114636).

Almost surely, 2^821366436 is an apocalyptic number.

It is an amenable number.

821366436 is an abundant number, since it is smaller than the sum of its proper divisors (1269384828).

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

821366436 is a wasteful number, since it uses less digits than its factorization.

821366436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6222491 (or 6222489 counting only the distinct ones).

The product of its digits is 124416, while the sum is 39.

The square root of 821366436 is about 28659.4912027412. The cubic root of 821366436 is about 936.5097805625.

The spelling of 821366436 in words is "eight hundred twenty-one million, three hundred sixty-six thousand, four hundred thirty-six".