425640634 has 4 divisors (see below), whose sum is σ = 638460954. Its totient is φ = 212820316.

The previous prime is 425640629. The next prime is 425640643. The reversal of 425640634 is 436046524.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 424236409 + 1404225 = 20597^2 + 1185^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 425640634.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106410157 + ... + 106410160.

Almost surely, 2^425640634 is an apocalyptic number.

425640634 is a deficient number, since it is larger than the sum of its proper divisors (212820320).

425640634 is a wasteful number, since it uses less digits than its factorization.

425640634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212820319.

The product of its (nonzero) digits is 69120, while the sum is 34.

The square root of 425640634 is about 20631.0599339927. The cubic root of 425640634 is about 752.2248801660.

The spelling of 425640634 in words is "four hundred twenty-five million, six hundred forty thousand, six hundred thirty-four".