1278652815421 has 8 divisors (see below), whose sum is σ = 1280910494304. Its totient is φ = 1276395407760.

The previous prime is 1278652815409. The next prime is 1278652815443. The reversal of 1278652815421 is 1245182568721.

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 1278652815421 - 2¹⁷ = 1278652684349 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 (1278652815821) 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, 10936951 + ... + 11053243.

It is an arithmetic number, because the mean of its divisors is an integer number (160113811788).

Almost surely, 2^{1278652815421} is an apocalyptic number.

It is an amenable number.

1278652815421 is a deficient number, since it is larger than the sum of its proper divisors (2257678883).

1278652815421 is a wasteful number, since it uses less digits than its factorization.

1278652815421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135611.

The product of its digits is 2150400, while the sum is 52.

The spelling of 1278652815421 in words is "one trillion, two hundred seventy-eight billion, six hundred fifty-two million, eight hundred fifteen thousand, four hundred twenty-one".