20216451 has 16 divisors (see below), whose sum is σ = 29527200. Its totient is φ = 12246528.

The previous prime is 20216447. The next prime is 20216477. The reversal of 20216451 is 15461202.

It is not a de Polignac number, because 20216451 - 2² = 20216447 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20216411) 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, 5356 + ... + 8313.

It is an arithmetic number, because the mean of its divisors is an integer number (1845450).

Almost surely, 2^20216451 is an apocalyptic number.

20216451 is a deficient number, since it is larger than the sum of its proper divisors (9310749).

20216451 is a wasteful number, since it uses less digits than its factorization.

20216451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13718.

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 20216451 is about 4496.2707881087. The cubic root of 20216451 is about 272.4174808355.

Adding to 20216451 its reverse (15461202), we get a palindrome (35677653).

It can be divided in two parts, 202 and 16451, that added together give a triangular number (16653 = T₁₈₂).

The spelling of 20216451 in words is "twenty million, two hundred sixteen thousand, four hundred fifty-one".