685545401 has 4 divisors (see below), whose sum is σ = 690778704. Its totient is φ = 680312100.

The previous prime is 685545391. The next prime is 685545481. The reversal of 685545401 is 104545586.

It is a happy number.

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: 104545586 = 2 ⋅52272793.

It is a cyclic number.

It is not a de Polignac number, because 685545401 - 2¹⁴ = 685529017 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (685545481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2616455 + ... + 2616716.

It is an arithmetic number, because the mean of its divisors is an integer number (172694676).

Almost surely, 2^685545401 is an apocalyptic number.

It is an amenable number.

685545401 is a deficient number, since it is larger than the sum of its proper divisors (5233303).

685545401 is a wasteful number, since it uses less digits than its factorization.

685545401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5233302.

The product of its (nonzero) digits is 96000, while the sum is 38.

The square root of 685545401 is about 26182.9219339630. The cubic root of 685545401 is about 881.7498759418.

The spelling of 685545401 in words is "six hundred eighty-five million, five hundred forty-five thousand, four hundred one".