1540421 has 16 divisors (see below), whose sum is σ = 1751040. Its totient is φ = 1347840.

The previous prime is 1540403. The next prime is 1540423. The reversal of 1540421 is 1240451.

It is a cyclic number.

It is not a de Polignac number, because 1540421 - 2¹⁰ = 1539397 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1540421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1540423) 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, 19460 + ... + 19538.

It is an arithmetic number, because the mean of its divisors is an integer number (109440).

2^1540421 is an apocalyptic number.

It is an amenable number.

1540421 is a deficient number, since it is larger than the sum of its proper divisors (210619).

1540421 is a wasteful number, since it uses less digits than its factorization.

1540421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164.

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 1540421 is about 1241.1369787417. The cubic root of 1540421 is about 115.4905572511.

Adding to 1540421 its reverse (1240451), we get a palindrome (2780872).

The spelling of 1540421 in words is "one million, five hundred forty thousand, four hundred twenty-one".