20355451 has 4 divisors (see below), whose sum is σ = 20387752. Its totient is φ = 20323152.

The previous prime is 20355431. The next prime is 20355473. The reversal of 20355451 is 15455302.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20355451 - 2¹³ = 20347259 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20355431) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15186 + ... + 16471.

It is an arithmetic number, because the mean of its divisors is an integer number (5096938).

Almost surely, 2^20355451 is an apocalyptic number.

20355451 is a deficient number, since it is larger than the sum of its proper divisors (32301).

20355451 is an equidigital number, since it uses as much as digits as its factorization.

20355451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32300.

The product of its (nonzero) digits is 3000, while the sum is 25.

The square root of 20355451 is about 4511.7015637119. The cubic root of 20355451 is about 273.0403988750.

The spelling of 20355451 in words is "twenty million, three hundred fifty-five thousand, four hundred fifty-one".