1201531505 has 4 divisors (see below), whose sum is σ = 1441837812. Its totient is φ = 961225200.

The previous prime is 1201531447. The next prime is 1201531549. The reversal of 1201531505 is 5051351021.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 874030096 + 327501409 = 29564^2 + 18097^2 .

It is not a de Polignac number, because 1201531505 - 2¹² = 1201527409 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 120153146 + ... + 120153155.

It is an arithmetic number, because the mean of its divisors is an integer number (360459453).

Almost surely, 2^1201531505 is an apocalyptic number.

It is an amenable number.

1201531505 is a deficient number, since it is larger than the sum of its proper divisors (240306307).

1201531505 is an equidigital number, since it uses as much as digits as its factorization.

1201531505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240306306.

The product of its (nonzero) digits is 750, while the sum is 23.

The square root of 1201531505 is about 34663.1144734572. The cubic root of 1201531505 is about 1063.1104511406.

Adding to 1201531505 its reverse (5051351021), we get a palindrome (6252882526).

The spelling of 1201531505 in words is "one billion, two hundred one million, five hundred thirty-one thousand, five hundred five".