15540493 has 2 divisors, whose sum is σ = 15540494. Its totient is φ = 15540492.

The previous prime is 15540487. The next prime is 15540509. The reversal of 15540493 is 39404551.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7823209 + 7717284 = 2797^2 + 2778^2 .

It is a cyclic number.

It is not a de Polignac number, because 15540493 - 2¹⁷ = 15409421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15540593) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7770246 + 7770247.

It is an arithmetic number, because the mean of its divisors is an integer number (7770247).

Almost surely, 2^15540493 is an apocalyptic number.

It is an amenable number.

15540493 is a deficient number, since it is larger than the sum of its proper divisors (1).

15540493 is an equidigital number, since it uses as much as digits as its factorization.

15540493 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10800, while the sum is 31.

The square root of 15540493 is about 3942.1431988196. The cubic root of 15540493 is about 249.5484810134.

The spelling of 15540493 in words is "fifteen million, five hundred forty thousand, four hundred ninety-three".