221400123 has 32 divisors (see below), whose sum is σ = 357557760. Its totient is φ = 119159040.

The previous prime is 221400121. The next prime is 221400131. The reversal of 221400123 is 321004122.

221400123 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 221400123 - 2¹ = 221400121 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221400121) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20536 + ... + 29402.

It is an arithmetic number, because the mean of its divisors is an integer number (11173680).

Almost surely, 2^221400123 is an apocalyptic number.

221400123 is a deficient number, since it is larger than the sum of its proper divisors (136157637).

221400123 is a wasteful number, since it uses less digits than its factorization.

221400123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8947.

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 221400123 is about 14879.5202543630. The cubic root of 221400123 is about 604.9590145948.

Adding to 221400123 its reverse (321004122), we get a palindrome (542404245).

The spelling of 221400123 in words is "two hundred twenty-one million, four hundred thousand, one hundred twenty-three".