1275816125021 has 16 divisors (see below), whose sum is σ = 1306494576000. Its totient is φ = 1245443976000.

The previous prime is 1275816124993. The next prime is 1275816125053. The reversal of 1275816125021 is 1205216185721.

It is a cyclic number.

It is not a de Polignac number, because 1275816125021 - 2²² = 1275811930717 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1275816125021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1275816125821) 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, 37177571 + ... + 37211871.

It is an arithmetic number, because the mean of its divisors is an integer number (81655911000).

Almost surely, 2^{1275816125021} is an apocalyptic number.

It is an amenable number.

1275816125021 is a deficient number, since it is larger than the sum of its proper divisors (30678450979).

1275816125021 is a wasteful number, since it uses less digits than its factorization.

1275816125021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38740.

The product of its (nonzero) digits is 67200, while the sum is 41.

The spelling of 1275816125021 in words is "one trillion, two hundred seventy-five billion, eight hundred sixteen million, one hundred twenty-five thousand, twenty-one".