21404010 has 16 divisors (see below), whose sum is σ = 51369696. Its totient is φ = 5707728.

The previous prime is 21403979. The next prime is 21404017. The reversal of 21404010 is 1040412.

It is not an unprimeable number, because it can be changed into a prime (21404017) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 356704 + ... + 356763.

It is an arithmetic number, because the mean of its divisors is an integer number (3210606).

Almost surely, 2^21404010 is an apocalyptic number.

21404010 is an abundant number, since it is smaller than the sum of its proper divisors (29965686).

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

21404010 is a wasteful number, since it uses less digits than its factorization.

21404010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 713477.

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 21404010 is about 4626.4468007316. The cubic root of 21404010 is about 277.6504500296.

Adding to 21404010 its reverse (1040412), we get a palindrome (22444422).

The spelling of 21404010 in words is "twenty-one million, four hundred four thousand, ten".