686821050 has 36 divisors (see below), whose sum is σ = 1845260430. Its totient is φ = 183152160.

The previous prime is 686821039. The next prime is 686821061. The reversal of 686821050 is 50128686.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (686821039) and next prime (686821061).

It can be written as a sum of positive squares in 3 ways, for example, as 255968001 + 430853049 = 15999^2 + 20757^2 .

It is a junction number, because it is equal to n+sod(n) for n = 686820996 and 686821014.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 762685 + ... + 763584.

Almost surely, 2^686821050 is an apocalyptic number.

686821050 is an abundant number, since it is smaller than the sum of its proper divisors (1158439380).

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

686821050 is a wasteful number, since it uses less digits than its factorization.

686821050 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1526287 (or 1526279 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 686821050 is about 26207.2709376616. The cubic root of 686821050 is about 882.2964511678.

The spelling of 686821050 in words is "six hundred eighty-six million, eight hundred twenty-one thousand, fifty".