1540215331 has 4 divisors (see below), whose sum is σ = 1545658072. Its totient is φ = 1534772592.

The previous prime is 1540215329. The next prime is 1540215343. The reversal of 1540215331 is 1335120451.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1335120451 = 7 ⋅190731493.

It is a cyclic number.

It is not a de Polignac number, because 1540215331 - 2¹ = 1540215329 is a prime.

It is a super-2 number, since 2×1540215331² = 4744526531694879122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1540215296 and 1540215305.

It is not an unprimeable number, because it can be changed into a prime (1540215311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2720946 + ... + 2721511.

It is an arithmetic number, because the mean of its divisors is an integer number (386414518).

Almost surely, 2^1540215331 is an apocalyptic number.

1540215331 is a deficient number, since it is larger than the sum of its proper divisors (5442741).

1540215331 is an equidigital number, since it uses as much as digits as its factorization.

1540215331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5442740.

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 1540215331 is about 39245.5772157832. The cubic root of 1540215331 is about 1154.8541712278.

Adding to 1540215331 its reverse (1335120451), we get a palindrome (2875335782).

The spelling of 1540215331 in words is "one billion, five hundred forty million, two hundred fifteen thousand, three hundred thirty-one".