1261538701 has 8 divisors (see below), whose sum is σ = 1286087544. Its totient is φ = 1237017600.

The previous prime is 1261538699. The next prime is 1261538741. The reversal of 1261538701 is 1078351621.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 540562500 + 720976201 = 23250^2 + 26851^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1261538701 - 2¹ = 1261538699 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 (1261538741) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 101001 + ... + 112801.

It is an arithmetic number, because the mean of its divisors is an integer number (160760943).

Almost surely, 2^1261538701 is an apocalyptic number.

It is an amenable number.

1261538701 is a deficient number, since it is larger than the sum of its proper divisors (24548843).

1261538701 is a wasteful number, since it uses less digits than its factorization.

1261538701 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13871.

The product of its (nonzero) digits is 10080, while the sum is 34.

The square root of 1261538701 is about 35518.1460805600. The cubic root of 1261538701 is about 1080.5217817638.

The spelling of 1261538701 in words is "one billion, two hundred sixty-one million, five hundred thirty-eight thousand, seven hundred one".