1252707678781 has 16 divisors (see below), whose sum is σ = 1350557513200. Its totient is φ = 1155070844928.

The previous prime is 1252707678769. The next prime is 1252707678821. The reversal of 1252707678781 is 1878767072521.

It can be written as a sum of positive squares in 8 ways, for example, as 377985188025 + 874722490756 = 614805^2 + 935266^2 .

It is not a de Polignac number, because 1252707678781 - 2²¹ = 1252705581629 is a prime.

It is a super-2 number, since 2×1252707678781² (a number of 25 digits) contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1252707678721) 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, 128228065 + ... + 128237833.

It is an arithmetic number, because the mean of its divisors is an integer number (84409844575).

Almost surely, 2^{1252707678781} is an apocalyptic number.

It is an amenable number.

1252707678781 is a deficient number, since it is larger than the sum of its proper divisors (97849834419).

1252707678781 is a wasteful number, since it uses less digits than its factorization.

1252707678781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19648.

The product of its (nonzero) digits is 18439680, while the sum is 61.

The spelling of 1252707678781 in words is "one trillion, two hundred fifty-two billion, seven hundred seven million, six hundred seventy-eight thousand, seven hundred eighty-one".