634245661 has 12 divisors (see below), whose sum is σ = 738778368. Its totient is φ = 542915352.

The previous prime is 634245653. The next prime is 634245679. The reversal of 634245661 is 166542436.

It is not a de Polignac number, because 634245661 - 2³ = 634245653 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 634245661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (634248661) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30340 + ... + 46786.

It is an arithmetic number, because the mean of its divisors is an integer number (61564864).

Almost surely, 2^634245661 is an apocalyptic number.

It is an amenable number.

634245661 is a deficient number, since it is larger than the sum of its proper divisors (104532707).

634245661 is a wasteful number, since it uses less digits than its factorization.

634245661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17248 (or 17241 counting only the distinct ones).

The product of its digits is 103680, while the sum is 37.

The square root of 634245661 is about 25184.2343739094. The cubic root of 634245661 is about 859.1833156452.

It can be divided in two parts, 6342 and 45661, that added together give a triangular number (52003 = T₃₂₂).

The spelling of 634245661 in words is "six hundred thirty-four million, two hundred forty-five thousand, six hundred sixty-one".