820697436 has 72 divisors (see below), whose sum is σ = 2238519920. Its totient is φ = 252025344.

The previous prime is 820697411. The next prime is 820697459. The reversal of 820697436 is 634796028.

820697436 is a `hidden beast` number, since 8 + 206 + 9 + 7 + 436 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 820697391 and 820697400.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 288276 + ... + 291108.

Almost surely, 2^820697436 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 820697436, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1119259960).

820697436 is an abundant number, since it is smaller than the sum of its proper divisors (1417822484).

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

820697436 is a wasteful number, since it uses less digits than its factorization.

820697436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3475 (or 3470 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 45.

The square root of 820697436 is about 28647.8172990544. The cubic root of 820697436 is about 936.2554502200.

The spelling of 820697436 in words is "eight hundred twenty million, six hundred ninety-seven thousand, four hundred thirty-six".