21002434 has 8 divisors (see below), whose sum is σ = 31526928. Its totient is φ = 10493460.

The previous prime is 21002431. The next prime is 21002461. The reversal of 21002434 is 43420012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21002434² = 882204467848712, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21002431) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 489 + ... + 6499.

It is an arithmetic number, because the mean of its divisors is an integer number (3940866).

Almost surely, 2^21002434 is an apocalyptic number.

21002434 is a deficient number, since it is larger than the sum of its proper divisors (10524494).

21002434 is a wasteful number, since it uses less digits than its factorization.

21002434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7760.

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 21002434 is about 4582.8412584335. The cubic root of 21002434 is about 275.9030763080.

Adding to 21002434 its reverse (43420012), we get a palindrome (64422446).

The spelling of 21002434 in words is "twenty-one million, two thousand, four hundred thirty-four".