634681405 has 8 divisors (see below), whose sum is σ = 762051384. Its totient is φ = 507456000.

The previous prime is 634681403. The next prime is 634681429. The reversal of 634681405 is 504186436.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 117983044 + 516698361 = 10862^2 + 22731^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 634681405 - 2¹ = 634681403 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (634681403) 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, 26236 + ... + 44245.

It is an arithmetic number, because the mean of its divisors is an integer number (95256423).

Almost surely, 2^634681405 is an apocalyptic number.

It is an amenable number.

634681405 is a deficient number, since it is larger than the sum of its proper divisors (127369979).

634681405 is a wasteful number, since it uses less digits than its factorization.

634681405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72287.

The product of its (nonzero) digits is 69120, while the sum is 37.

The square root of 634681405 is about 25192.8840151341. The cubic root of 634681405 is about 859.3800313623.

The spelling of 634681405 in words is "six hundred thirty-four million, six hundred eighty-one thousand, four hundred five".