40123421 has 16 divisors (see below), whose sum is σ = 46247040. Its totient is φ = 34499520.

The previous prime is 40123411. The next prime is 40123439. The reversal of 40123421 is 12432104.

It is a cyclic number.

It is not a de Polignac number, because 40123421 - 2¹⁴ = 40107037 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 40123421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40123411) 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, 13736 + ... + 16398.

It is an arithmetic number, because the mean of its divisors is an integer number (2890440).

Almost surely, 2^40123421 is an apocalyptic number.

It is an amenable number.

40123421 is a deficient number, since it is larger than the sum of its proper divisors (6123619).

40123421 is a wasteful number, since it uses less digits than its factorization.

40123421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2756.

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 40123421 is about 6334.3050921155. The cubic root of 40123421 is about 342.3465730838.

Adding to 40123421 its reverse (12432104), we get a palindrome (52555525).

The spelling of 40123421 in words is "forty million, one hundred twenty-three thousand, four hundred twenty-one".