21730434 has 32 divisors (see below), whose sum is σ = 47601216. Its totient is φ = 6558720.

The previous prime is 21730417. The next prime is 21730439. The reversal of 21730434 is 43403712.

It is not an unprimeable number, because it can be changed into a prime (21730439) 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, 21754 + ... + 22730.

It is an arithmetic number, because the mean of its divisors is an integer number (1487538).

Almost surely, 2^21730434 is an apocalyptic number.

21730434 is an abundant number, since it is smaller than the sum of its proper divisors (25870782).

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

21730434 is a wasteful number, since it uses less digits than its factorization.

21730434 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1330.

The product of its (nonzero) digits is 2016, while the sum is 24.

The square root of 21730434 is about 4661.5913591820. The cubic root of 21730434 is about 279.0547804203.

The spelling of 21730434 in words is "twenty-one million, seven hundred thirty thousand, four hundred thirty-four".