21420234234 has 24 divisors (see below), whose sum is σ = 53040580320. Its totient is φ = 6120066888.

The previous prime is 21420234211. The next prime is 21420234257. The reversal of 21420234234 is 43243202412.

21420234234 is a `hidden beast` number, since 2 + 1 + 420 + 2 + 3 + 4 + 234 = 666.

It is an interprime number because it is at equal distance from previous prime (21420234211) and next prime (21420234257).

It is a junction number, because it is equal to n+sod(n) for n = 21420234198 and 21420234207.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 85000804 + ... + 85001055.

It is an arithmetic number, because the mean of its divisors is an integer number (2210024180).

Almost surely, 2^21420234234 is an apocalyptic number.

21420234234 is an abundant number, since it is smaller than the sum of its proper divisors (31620346086).

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

21420234234 is a wasteful number, since it uses less digits than its factorization.

21420234234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170001874 (or 170001871 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 27.

Adding to 21420234234 its reverse (43243202412), we get a palindrome (64663436646).

The spelling of 21420234234 in words is "twenty-one billion, four hundred twenty million, two hundred thirty-four thousand, two hundred thirty-four".