30000000021 has 16 divisors (see below), whose sum is σ = 41757553536. Its totient is φ = 19121990976.

The previous prime is 30000000013. The next prime is 30000000053. The reversal of 30000000021 is 12000000003.

It is not a de Polignac number, because 30000000021 - 2³ = 30000000013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 29999999937 and 30000000009.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30000000001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 63411 + ... + 253023.

It is an arithmetic number, because the mean of its divisors is an integer number (2609847096).

Almost surely, 2^30000000021 is an apocalyptic number.

It is an amenable number.

30000000021 is a deficient number, since it is larger than the sum of its proper divisors (11757553515).

30000000021 is a wasteful number, since it uses less digits than its factorization.

30000000021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191932.

The product of its (nonzero) digits is 6, while the sum is 6.

Adding to 30000000021 its reverse (12000000003), we get a palindrome (42000000024).

It can be divided in two parts, 3000000002 and 1, that added together give a palindrome (3000000003).

The spelling of 30000000021 in words is "thirty billion, twenty-one", and thus it is an aban number and an uban number.