126403921 has 8 divisors (see below), whose sum is σ = 145787840. Its totient is φ = 107351568.

The previous prime is 126403913. The next prime is 126403973. The reversal of 126403921 is 129304621.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 126403921 - 2³ = 126403913 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 126403921.

It is not an unprimeable number, because it can be changed into a prime (126403421) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 82071 + ... + 83596.

It is an arithmetic number, because the mean of its divisors is an integer number (18223480).

Almost surely, 2^126403921 is an apocalyptic number.

It is an amenable number.

126403921 is a deficient number, since it is larger than the sum of its proper divisors (19383919).

126403921 is a wasteful number, since it uses less digits than its factorization.

126403921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165783.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 126403921 is about 11242.9498353413. The cubic root of 126403921 is about 501.8649300900.

It can be divided in two parts, 12640 and 3921, that added together give a palindrome (16561).

The spelling of 126403921 in words is "one hundred twenty-six million, four hundred three thousand, nine hundred twenty-one".