1261257333541 has 16 divisors (see below), whose sum is σ = 1276249822848. Its totient is φ = 1246358145600.

The previous prime is 1261257333529. The next prime is 1261257333559. The reversal of 1261257333541 is 1453337521621.

It is a cyclic number.

It is not a de Polignac number, because 1261257333541 - 2⁵ = 1261257333509 is a prime.

It is a super-3 number, since 3×1261257333541³ (a number of 37 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261257333241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 128550526 + ... + 128560336.

It is an arithmetic number, because the mean of its divisors is an integer number (79765613928).

Almost surely, 2^{1261257333541} is an apocalyptic number.

It is an amenable number.

1261257333541 is a deficient number, since it is larger than the sum of its proper divisors (14992489307).

1261257333541 is a wasteful number, since it uses less digits than its factorization.

1261257333541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14412.

The product of its digits is 453600, while the sum is 43.

The spelling of 1261257333541 in words is "one trillion, two hundred sixty-one billion, two hundred fifty-seven million, three hundred thirty-three thousand, five hundred forty-one".