21354770 has 16 divisors (see below), whose sum is σ = 38515608. Its totient is φ = 8524800.

The previous prime is 21354721. The next prime is 21354797. The reversal of 21354770 is 7745312.

It can be written as a sum of positive squares in 4 ways, for example, as 20802721 + 552049 = 4561^2 + 743^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3920 + ... + 7620.

Almost surely, 2^21354770 is an apocalyptic number.

21354770 is a deficient number, since it is larger than the sum of its proper divisors (17160838).

21354770 is a wasteful number, since it uses less digits than its factorization.

21354770 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4285.

The product of its (nonzero) digits is 5880, while the sum is 29.

The square root of 21354770 is about 4621.1221580910. The cubic root of 21354770 is about 277.4373746080.

The spelling of 21354770 in words is "twenty-one million, three hundred fifty-four thousand, seven hundred seventy".