21634142 has 16 divisors (see below), whose sum is σ = 33439392. Its totient is φ = 10490880.

The previous prime is 21634139. The next prime is 21634153. The reversal of 21634142 is 24143612.

It is a super-2 number, since 2×21634142² = 936072200152328, which contains 22 as substring.

It is a congruent number.

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, 15143 + ... + 16509.

It is an arithmetic number, because the mean of its divisors is an integer number (2089962).

Almost surely, 2^21634142 is an apocalyptic number.

21634142 is a deficient number, since it is larger than the sum of its proper divisors (11805250).

21634142 is a wasteful number, since it uses less digits than its factorization.

21634142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1603.

The product of its digits is 1152, while the sum is 23.

The square root of 21634142 is about 4651.2516594998. The cubic root of 21634142 is about 278.6419871487.

Adding to 21634142 its reverse (24143612), we get a palindrome (45777754).

The spelling of 21634142 in words is "twenty-one million, six hundred thirty-four thousand, one hundred forty-two".