21436574 has 4 divisors (see below), whose sum is σ = 32154864. Its totient is φ = 10718286.

The previous prime is 21436573. The next prime is 21436601. The reversal of 21436574 is 47563412.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21436574.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21436573) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5359142 + ... + 5359145.

It is an arithmetic number, because the mean of its divisors is an integer number (8038716).

Almost surely, 2^21436574 is an apocalyptic number.

21436574 is a deficient number, since it is larger than the sum of its proper divisors (10718290).

21436574 is a wasteful number, since it uses less digits than its factorization.

21436574 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10718289.

The product of its digits is 20160, while the sum is 32.

The square root of 21436574 is about 4629.9647946826. The cubic root of 21436574 is about 277.7911842181.

Adding to 21436574 its reverse (47563412), we get a palindrome (68999986).

The spelling of 21436574 in words is "twenty-one million, four hundred thirty-six thousand, five hundred seventy-four".