634021521 has 8 divisors (see below), whose sum is σ = 966128064. Its totient is φ = 362298000.

The previous prime is 634021471. The next prime is 634021543. The reversal of 634021521 is 125120436.

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

It is not a de Polignac number, because 634021521 - 2¹¹ = 634019473 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 634021491 and 634021500.

It is not an unprimeable number, because it can be changed into a prime (634021121) 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, 15095730 + ... + 15095771.

It is an arithmetic number, because the mean of its divisors is an integer number (120766008).

Almost surely, 2^634021521 is an apocalyptic number.

It is an amenable number.

634021521 is a deficient number, since it is larger than the sum of its proper divisors (332106543).

634021521 is a wasteful number, since it uses less digits than its factorization.

634021521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30191511.

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 634021521 is about 25179.7839744506. The cubic root of 634021521 is about 859.0820930170.

Adding to 634021521 its reverse (125120436), we get a palindrome (759141957).

The spelling of 634021521 in words is "six hundred thirty-four million, twenty-one thousand, five hundred twenty-one".