21434036 has 12 divisors (see below), whose sum is σ = 40395012. Its totient is φ = 9892608.

The previous prime is 21434029. The next prime is 21434047. The reversal of 21434036 is 63043412.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 11155600 + 10278436 = 3340^2 + 3206^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 206045 + ... + 206148.

It is an arithmetic number, because the mean of its divisors is an integer number (3366251).

Almost surely, 2^21434036 is an apocalyptic number.

21434036 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21434036 is a deficient number, since it is larger than the sum of its proper divisors (18960976).

21434036 is a wasteful number, since it uses less digits than its factorization.

21434036 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 412210 (or 412208 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 23.

The square root of 21434036 is about 4629.6907024120. The cubic root of 21434036 is about 277.7802206837.

Adding to 21434036 its reverse (63043412), we get a palindrome (84477448).

The spelling of 21434036 in words is "twenty-one million, four hundred thirty-four thousand, thirty-six".