123421540 has 48 divisors (see below), whose sum is σ = 291884544. Its totient is φ = 43430400.

The previous prime is 123421523. The next prime is 123421541. The reversal of 123421540 is 45124321.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is not an unprimeable number, because it can be changed into a prime (123421541) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2229 + ... + 15868.

It is an arithmetic number, because the mean of its divisors is an integer number (6080928).

Almost surely, 2^123421540 is an apocalyptic number.

123421540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

123421540 is an abundant number, since it is smaller than the sum of its proper divisors (168463004).

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

123421540 is a wasteful number, since it uses less digits than its factorization.

123421540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18148 (or 18146 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 123421540 is about 11109.5247423101. The cubic root of 123421540 is about 497.8864651962.

Adding to 123421540 its reverse (45124321), we get a palindrome (168545861).

The spelling of 123421540 in words is "one hundred twenty-three million, four hundred twenty-one thousand, five hundred forty".