21081410 has 32 divisors (see below), whose sum is σ = 43528320. Its totient is φ = 7201152.

The previous prime is 21081397. The next prime is 21081413. The reversal of 21081410 is 1418012.

It is not an unprimeable number, because it can be changed into a prime (21081413) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31661 + ... + 32319.

It is an arithmetic number, because the mean of its divisors is an integer number (1360260).

Almost surely, 2^21081410 is an apocalyptic number.

21081410 is an abundant number, since it is smaller than the sum of its proper divisors (22446910).

21081410 is a wasteful number, since it uses less digits than its factorization.

21081410 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1130.

The product of its (nonzero) digits is 64, while the sum is 17.

The square root of 21081410 is about 4591.4496621438. The cubic root of 21081410 is about 276.2484722451.

Adding to 21081410 its reverse (1418012), we get a palindrome (22499422).

The spelling of 21081410 in words is "twenty-one million, eighty-one thousand, four hundred ten".