10405921 has 4 divisors (see below), whose sum is σ = 11018052. Its totient is φ = 9793792.

The previous prime is 10405897. The next prime is 10405949. The reversal of 10405921 is 12950401.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12950401 = 317 ⋅40853.

It can be written as a sum of positive squares in 2 ways, for example, as 8767521 + 1638400 = 2961^2 + 1280^2 .

It is a cyclic number.

It is not a de Polignac number, because 10405921 - 2¹⁹ = 9881633 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 10405892 and 10405901.

It is not an unprimeable number, because it can be changed into a prime (10405961) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 306040 + ... + 306073.

It is an arithmetic number, because the mean of its divisors is an integer number (2754513).

Almost surely, 2^10405921 is an apocalyptic number.

It is an amenable number.

10405921 is a deficient number, since it is larger than the sum of its proper divisors (612131).

10405921 is an equidigital number, since it uses as much as digits as its factorization.

10405921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 612130.

The product of its (nonzero) digits is 360, while the sum is 22.

The square root of 10405921 is about 3225.8209807737. The cubic root of 10405921 is about 218.3199927102.

The spelling of 10405921 in words is "ten million, four hundred five thousand, nine hundred twenty-one".