140815391 has 4 divisors (see below), whose sum is σ = 140961384. Its totient is φ = 140669400.

The previous prime is 140815351. The next prime is 140815399. The reversal of 140815391 is 193518041.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 193518041 = 1103 ⋅175447.

It is a cyclic number.

It is not a de Polignac number, because 140815391 - 2¹⁸ = 140553247 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (140815399) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71540 + ... + 73481.

It is an arithmetic number, because the mean of its divisors is an integer number (35240346).

Almost surely, 2^140815391 is an apocalyptic number.

140815391 is a deficient number, since it is larger than the sum of its proper divisors (145993).

140815391 is an equidigital number, since it uses as much as digits as its factorization.

140815391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145992.

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 140815391 is about 11866.5660997611. The cubic root of 140815391 is about 520.2555339239.

The spelling of 140815391 in words is "one hundred forty million, eight hundred fifteen thousand, three hundred ninety-one".