1540001 has 4 divisors (see below), whose sum is σ = 1577604. Its totient is φ = 1502400.

The previous prime is 1539997. The next prime is 1540003. The reversal of 1540001 is 1000451.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1000451 = 563 ⋅1777.

It can be written as a sum of positive squares in 2 ways, for example, as 102400 + 1437601 = 320^2 + 1199^2 .

It is a cyclic number.

It is not a de Polignac number, because 1540001 - 2² = 1539997 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1540003) 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, 18740 + ... + 18821.

It is an arithmetic number, because the mean of its divisors is an integer number (394401).

2^1540001 is an apocalyptic number.

It is an amenable number.

1540001 is a deficient number, since it is larger than the sum of its proper divisors (37603).

1540001 is an equidigital number, since it uses as much as digits as its factorization.

1540001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37602.

The product of its (nonzero) digits is 20, while the sum is 11.

The square root of 1540001 is about 1240.9677675105. The cubic root of 1540001 is about 115.4800600248.

Adding to 1540001 its reverse (1000451), we get a palindrome (2540452).

The spelling of 1540001 in words is "one million, five hundred forty thousand, one".