1240541551 has 4 divisors (see below), whose sum is σ = 1270798704. Its totient is φ = 1210284400.

The previous prime is 1240541473. The next prime is 1240541563. The reversal of 1240541551 is 1551450421.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1551450421 = 3299 ⋅470279.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1240541551 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 (1240541251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15128515 + ... + 15128596.

It is an arithmetic number, because the mean of its divisors is an integer number (317699676).

Almost surely, 2^1240541551 is an apocalyptic number.

1240541551 is a deficient number, since it is larger than the sum of its proper divisors (30257153).

1240541551 is an equidigital number, since it uses as much as digits as its factorization.

1240541551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30257152.

The product of its (nonzero) digits is 4000, while the sum is 28.

The square root of 1240541551 is about 35221.3223914151. The cubic root of 1240541551 is about 1074.4934483108.

Adding to 1240541551 its reverse (1551450421), we get a palindrome (2791991972).

It can be divided in two parts, 12405 and 41551, that added together give a triangular number (53956 = T₃₂₈).

The spelling of 1240541551 in words is "one billion, two hundred forty million, five hundred forty-one thousand, five hundred fifty-one".