21420234207 has 24 divisors (see below), whose sum is σ = 31963176960. Its totient is φ = 13808791440.

The previous prime is 21420234181. The next prime is 21420234211. The reversal of 21420234207 is 70243202412.

21420234207 is a `hidden beast` number, since 2 + 1 + 420 + 2 + 34 + 207 = 666.

It is not a de Polignac number, because 21420234207 - 2⁸ = 21420233951 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21420234257) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 338898 + ... + 397104.

It is an arithmetic number, because the mean of its divisors is an integer number (1331799040).

Almost surely, 2^21420234207 is an apocalyptic number.

21420234207 is a deficient number, since it is larger than the sum of its proper divisors (10542942753).

21420234207 is a wasteful number, since it uses less digits than its factorization.

21420234207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59563 (or 59560 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 27.

Adding to 21420234207 its reverse (70243202412), we get a palindrome (91663436619).

The spelling of 21420234207 in words is "twenty-one billion, four hundred twenty million, two hundred thirty-four thousand, two hundred seven".