21379434 has 16 divisors (see below), whose sum is σ = 43097088. Its totient is φ = 7070112.

The previous prime is 21379399. The next prime is 21379441. The reversal of 21379434 is 43497312.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21379395 and 21379404.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13267 + ... + 14790.

It is an arithmetic number, because the mean of its divisors is an integer number (2693568).

Almost surely, 2^21379434 is an apocalyptic number.

21379434 is an abundant number, since it is smaller than the sum of its proper divisors (21717654).

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

21379434 is a wasteful number, since it uses less digits than its factorization.

21379434 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28189.

The product of its digits is 18144, while the sum is 33.

The square root of 21379434 is about 4623.7900038821. The cubic root of 21379434 is about 277.5441436146.

The spelling of 21379434 in words is "twenty-one million, three hundred seventy-nine thousand, four hundred thirty-four".