210400055 has 4 divisors (see below), whose sum is σ = 252480072. Its totient is φ = 168320040.

The previous prime is 210400049. The next prime is 210400097. The reversal of 210400055 is 550004012.

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

It is not a de Polignac number, because 210400055 - 2⁴ = 210400039 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21040001 + ... + 21040010.

It is an arithmetic number, because the mean of its divisors is an integer number (63120018).

Almost surely, 2^210400055 is an apocalyptic number.

210400055 is a deficient number, since it is larger than the sum of its proper divisors (42080017).

210400055 is an equidigital number, since it uses as much as digits as its factorization.

210400055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42080016.

The product of its (nonzero) digits is 200, while the sum is 17.

The square root of 210400055 is about 14505.1733874504. The cubic root of 210400055 is about 594.7693996113.

Adding to 210400055 its reverse (550004012), we get a palindrome (760404067).

The spelling of 210400055 in words is "two hundred ten million, four hundred thousand, fifty-five".