210138723 has 12 divisors (see below), whose sum is σ = 305572800. Its totient is φ = 139151376.

The previous prime is 210138703. The next prime is 210138743. The reversal of 210138723 is 327831012.

210138723 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (210138703) and next prime (210138743).

It is not a de Polignac number, because 210138723 - 2⁶ = 210138659 is a prime.

It is not an unprimeable number, because it can be changed into a prime (210138703) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 77011 + ... + 79692.

It is an arithmetic number, because the mean of its divisors is an integer number (25464400).

Almost surely, 2^210138723 is an apocalyptic number.

210138723 is a deficient number, since it is larger than the sum of its proper divisors (95434077).

210138723 is a wasteful number, since it uses less digits than its factorization.

210138723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156858 (or 156855 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 210138723 is about 14496.1623542233. The cubic root of 210138723 is about 594.5230487982.

Adding to 210138723 its reverse (327831012), we get a palindrome (537969735).

The spelling of 210138723 in words is "two hundred ten million, one hundred thirty-eight thousand, seven hundred twenty-three".