1542243917 has 4 divisors (see below), whose sum is σ = 1563370620. Its totient is φ = 1521117216.

The previous prime is 1542243877. The next prime is 1542243919. The reversal of 1542243917 is 7193422451.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7193422451 = 37 ⋅194416823.

It can be written as a sum of positive squares in 2 ways, for example, as 472888516 + 1069355401 = 21746^2 + 32701^2 .

It is a cyclic number.

It is not a de Polignac number, because 1542243917 - 2¹⁰ = 1542242893 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 (1542243919) 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, 10563242 + ... + 10563387.

It is an arithmetic number, because the mean of its divisors is an integer number (390842655).

Almost surely, 2^1542243917 is an apocalyptic number.

It is an amenable number.

1542243917 is a deficient number, since it is larger than the sum of its proper divisors (21126703).

1542243917 is an equidigital number, since it uses as much as digits as its factorization.

1542243917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21126702.

The product of its digits is 60480, while the sum is 38.

The square root of 1542243917 is about 39271.4134836015. The cubic root of 1542243917 is about 1155.3609603743.

The spelling of 1542243917 in words is "one billion, five hundred forty-two million, two hundred forty-three thousand, nine hundred seventeen".