1511661241 has 4 divisors (see below), whose sum is σ = 1511739684. Its totient is φ = 1511582800.

The previous prime is 1511661227. The next prime is 1511661247. The reversal of 1511661241 is 1421661151.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 170563600 + 1341097641 = 13060^2 + 36621^2 .

It is a cyclic number.

It is not a de Polignac number, because 1511661241 - 2⁵ = 1511661209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1511661247) 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, 11871 + ... + 56251.

It is an arithmetic number, because the mean of its divisors is an integer number (377934921).

Almost surely, 2^1511661241 is an apocalyptic number.

It is an amenable number.

1511661241 is a deficient number, since it is larger than the sum of its proper divisors (78443).

1511661241 is an equidigital number, since it uses as much as digits as its factorization.

1511661241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78442.

The product of its digits is 1440, while the sum is 28.

The square root of 1511661241 is about 38880.0879757235. The cubic root of 1511661241 is about 1147.6729859787.

The spelling of 1511661241 in words is "one billion, five hundred eleven million, six hundred sixty-one thousand, two hundred forty-one".