23190840 has 128 divisors (see below), whose sum is σ = 78408000. Its totient is φ = 6096384.

The previous prime is 23190833. The next prime is 23190841. The reversal of 23190840 is 4809132.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23190841) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 117622 + ... + 117818.

Almost surely, 2^23190840 is an apocalyptic number.

23190840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 23190840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39204000).

23190840 is an abundant number, since it is smaller than the sum of its proper divisors (55217160).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

23190840 is a wasteful number, since it uses less digits than its factorization.

23190840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 326 (or 316 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 23190840 is about 4815.6868668966. The cubic root of 23190840 is about 285.1710884091.

Adding to 23190840 its reverse (4809132), we get a palindrome (27999972).

The spelling of 23190840 in words is "twenty-three million, one hundred ninety thousand, eight hundred forty".