30638651521 has 3 divisors (see below), whose sum is σ = 30638826561. Its totient is φ = 30638476482.

The previous prime is 30638651473. The next prime is 30638651587. The reversal of 30638651521 is 12515683603.

The square root of 30638651521 is 175039.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 30638651521 - 2⁹ = 30638651009 is a prime.

It is a super-2 number, since 2×30638651521² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (30638651221) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 87520 + ... + 262558.

It is an arithmetic number, because the mean of its divisors is an integer number (10212942187).

Almost surely, 2^30638651521 is an apocalyptic number.

30638651521 is the 175039-th square number.

30638651521 is the 87520-th centered octagonal number.

It is an amenable number.

30638651521 is a deficient number, since it is larger than the sum of its proper divisors (175040).

30638651521 is an frugal number, since it uses more digits than its factorization.

30638651521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 350078 (or 175039 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 40.

The spelling of 30638651521 in words is "thirty billion, six hundred thirty-eight million, six hundred fifty-one thousand, five hundred twenty-one".