30138723 has 20 divisors (see below), whose sum is σ = 45221088. Its totient is φ = 20003760.

The previous prime is 30138709. The next prime is 30138791. The reversal of 30138723 is 32783103.

It is not a de Polignac number, because 30138723 - 2⁶ = 30138659 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (30138023) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 21265 + ... + 22637.

Almost surely, 2^30138723 is an apocalyptic number.

30138723 is a deficient number, since it is larger than the sum of its proper divisors (15082365).

30138723 is a wasteful number, since it uses less digits than its factorization.

30138723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1656 (or 1647 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 27.

The square root of 30138723 is about 5489.8745887315. The cubic root of 30138723 is about 311.2014527273.

The spelling of 30138723 in words is "thirty million, one hundred thirty-eight thousand, seven hundred twenty-three".