634721040 has 120 divisors (see below), whose sum is σ = 2136196608. Its totient is φ = 168894720.

The previous prime is 634721039. The next prime is 634721053. The reversal of 634721040 is 40127436.

634721040 is a `hidden beast` number, since 634 + 7 + 21 + 0 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (120).

It is a junction number, because it is equal to n+sod(n) for n = 634720995 and 634721013.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 583377 + ... + 584463.

Almost surely, 2^634721040 is an apocalyptic number.

634721040 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 634721040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1068098304).

634721040 is an abundant number, since it is smaller than the sum of its proper divisors (1501475568).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

634721040 is a wasteful number, since it uses less digits than its factorization.

634721040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1917 (or 1908 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 27.

The square root of 634721040 is about 25193.6706337127. The cubic root of 634721040 is about 859.3979200322.

Adding to 634721040 its reverse (40127436), we get a palindrome (674848476).

The spelling of 634721040 in words is "six hundred thirty-four million, seven hundred twenty-one thousand, forty".