1265013400921 has 16 divisors (see below), whose sum is σ = 1294332353280. Its totient is φ = 1235796756480.

The previous prime is 1265013400909. The next prime is 1265013400933. The reversal of 1265013400921 is 1290043105621.

It is an interprime number because it is at equal distance from previous prime (1265013400909) and next prime (1265013400933).

It is a cyclic number.

It is not a de Polignac number, because 1265013400921 - 2³¹ = 1262865917273 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1265013401921) 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, 60053731 + ... + 60074791.

It is an arithmetic number, because the mean of its divisors is an integer number (80895772080).

Almost surely, 2^{1265013400921} is an apocalyptic number.

It is an amenable number.

1265013400921 is a deficient number, since it is larger than the sum of its proper divisors (29318952359).

1265013400921 is a wasteful number, since it uses less digits than its factorization.

1265013400921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23424.

The product of its (nonzero) digits is 12960, while the sum is 34.

The spelling of 1265013400921 in words is "one trillion, two hundred sixty-five billion, thirteen million, four hundred thousand, nine hundred twenty-one".