21434090 has 32 divisors (see below), whose sum is σ = 41065920. Its totient is φ = 8031744.

The previous prime is 21434053. The next prime is 21434099. The reversal of 21434090 is 9043412.

It is not an unprimeable number, because it can be changed into a prime (21434099) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17849 + ... + 19011.

It is an arithmetic number, because the mean of its divisors is an integer number (1283310).

Almost surely, 2^21434090 is an apocalyptic number.

21434090 is a deficient number, since it is larger than the sum of its proper divisors (19631830).

21434090 is a wasteful number, since it uses less digits than its factorization.

21434090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1286.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 21434090 is about 4629.6965343314. The cubic root of 21434090 is about 277.7804539594.

The spelling of 21434090 in words is "twenty-one million, four hundred thirty-four thousand, ninety".