1261501264 has 20 divisors (see below), whose sum is σ = 2465791956. Its totient is φ = 625167872.

The previous prime is 1261501261. The next prime is 1261501279. The reversal of 1261501264 is 4621051621.

It can be written as a sum of positive squares in 2 ways, for example, as 621006400 + 640494864 = 24920^2 + 25308^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261501261) 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, 347059 + ... + 350674.

Almost surely, 2^1261501264 is an apocalyptic number.

It is an amenable number.

1261501264 is a deficient number, since it is larger than the sum of its proper divisors (1204290692).

1261501264 is a wasteful number, since it uses less digits than its factorization.

1261501264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 697854 (or 697848 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 1261501264 is about 35517.6190643461. The cubic root of 1261501264 is about 1080.5110932572.

Adding to 1261501264 its reverse (4621051621), we get a palindrome (5882552885).

The spelling of 1261501264 in words is "one billion, two hundred sixty-one million, five hundred one thousand, two hundred sixty-four".