21170234 has 4 divisors (see below), whose sum is σ = 31755354. Its totient is φ = 10585116.

The previous prime is 21170231. The next prime is 21170239. The reversal of 21170234 is 43207112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 18464209 + 2706025 = 4297^2 + 1645^2 .

It is a super-2 number, since 2×21170234² = 896357615229512, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21170231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5292557 + ... + 5292560.

Almost surely, 2^21170234 is an apocalyptic number.

21170234 is a deficient number, since it is larger than the sum of its proper divisors (10585120).

21170234 is a wasteful number, since it uses less digits than its factorization.

21170234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10585119.

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 21170234 is about 4601.1122568353. The cubic root of 21170234 is about 276.6359085821.

Adding to 21170234 its reverse (43207112), we get a palindrome (64377346).

The spelling of 21170234 in words is "twenty-one million, one hundred seventy thousand, two hundred thirty-four".