20400455 has 8 divisors (see below), whose sum is σ = 24697872. Its totient is φ = 16175488.

The previous prime is 20400439. The next prime is 20400463. The reversal of 20400455 is 55400402.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20400455 - 2⁴ = 20400439 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17489 + ... + 18618.

It is an arithmetic number, because the mean of its divisors is an integer number (3087234).

Almost surely, 2^20400455 is an apocalyptic number.

20400455 is a deficient number, since it is larger than the sum of its proper divisors (4297417).

20400455 is a wasteful number, since it uses less digits than its factorization.

20400455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36225.

The product of its (nonzero) digits is 800, while the sum is 20.

The square root of 20400455 is about 4516.6862853202. The cubic root of 20400455 is about 273.2414730314.

Adding to 20400455 its reverse (55400402), we get a palindrome (75800857).

The spelling of 20400455 in words is "twenty million, four hundred thousand, four hundred fifty-five".