686780401 has 4 divisors (see below), whose sum is σ = 688264192. Its totient is φ = 685296612.

The previous prime is 686780387. The next prime is 686780453. The reversal of 686780401 is 104087686.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 104087686 = 2 ⋅52043843.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-686780401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (686780701) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 741201 + ... + 742126.

It is an arithmetic number, because the mean of its divisors is an integer number (172066048).

Almost surely, 2^686780401 is an apocalyptic number.

It is an amenable number.

686780401 is a deficient number, since it is larger than the sum of its proper divisors (1483791).

686780401 is a wasteful number, since it uses less digits than its factorization.

686780401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1483790.

The product of its (nonzero) digits is 64512, while the sum is 40.

The square root of 686780401 is about 26206.4953971339. The cubic root of 686780401 is about 882.2790448016.

The spelling of 686780401 in words is "six hundred eighty-six million, seven hundred eighty thousand, four hundred one".