1515440242 has 4 divisors (see below), whose sum is σ = 2273160366. Its totient is φ = 757720120.

The previous prime is 1515440219. The next prime is 1515440249. The reversal of 1515440242 is 2420445151.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 2420445151 = 47 ⋅51498833.

It can be written as a sum of positive squares in only one way, i.e., 1025216361 + 490223881 = 32019^2 + 22141^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1515440242.

It is not an unprimeable number, because it can be changed into a prime (1515440249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 378860059 + ... + 378860062.

Almost surely, 2^1515440242 is an apocalyptic number.

1515440242 is a deficient number, since it is larger than the sum of its proper divisors (757720124).

1515440242 is an equidigital number, since it uses as much as digits as its factorization.

1515440242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 757720123.

The product of its (nonzero) digits is 6400, while the sum is 28.

The square root of 1515440242 is about 38928.6557949282. The cubic root of 1515440242 is about 1148.6285458150.

Adding to 1515440242 its reverse (2420445151), we get a palindrome (3935885393).

The spelling of 1515440242 in words is "one billion, five hundred fifteen million, four hundred forty thousand, two hundred forty-two".