21143634 has 16 divisors (see below), whose sum is σ = 42699072. Its totient is φ = 6979248.

The previous prime is 21143623. The next prime is 21143651. The reversal of 21143634 is 43634112.

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, 16489 + ... + 17724.

It is an arithmetic number, because the mean of its divisors is an integer number (2668692).

Almost surely, 2^21143634 is an apocalyptic number.

21143634 is an abundant number, since it is smaller than the sum of its proper divisors (21555438).

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

21143634 is a wasteful number, since it uses less digits than its factorization.

21143634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34321.

The product of its digits is 1728, while the sum is 24.

The square root of 21143634 is about 4598.2207428526. The cubic root of 21143634 is about 276.5199974201.

Adding to 21143634 its reverse (43634112), we get a palindrome (64777746).

The spelling of 21143634 in words is "twenty-one million, one hundred forty-three thousand, six hundred thirty-four".