123432390 has 64 divisors (see below), whose sum is σ = 339793920. Its totient is φ = 31851360.

The previous prime is 123432377. The next prime is 123432391. The reversal of 123432390 is 93234321.

It is a happy number.

It is a super-2 number, since 2×123432390² = 30471109802224200, which contains 22 as substring.

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 (123432391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 997 + ... + 15743.

It is an arithmetic number, because the mean of its divisors is an integer number (5309280).

Almost surely, 2^123432390 is an apocalyptic number.

123432390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 123432390, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (169896960).

123432390 is an abundant number, since it is smaller than the sum of its proper divisors (216361530).

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

123432390 is a wasteful number, since it uses less digits than its factorization.

123432390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14794 (or 14788 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 27.

The square root of 123432390 is about 11110.0130512975. The cubic root of 123432390 is about 497.9010545185.

The spelling of 123432390 in words is "one hundred twenty-three million, four hundred thirty-two thousand, three hundred ninety".