1279975497840 has 480 divisors, whose sum is σ = 4805038457856. Its totient is φ = 314786165760.

The previous prime is 1279975497839. The next prime is 1279975497847. The reversal of 1279975497840 is 487945799721.

1279975497840 is a `hidden beast` number, since 1 + 2 + 7 + 9 + 9 + 7 + 549 + 78 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1279975497847) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 472837767 + ... + 472840473.

Almost surely, 2^{1279975497840} is an apocalyptic number.

1279975497840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1279975497840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2402519228928).

1279975497840 is an abundant number, since it is smaller than the sum of its proper divisors (3525062960016).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1279975497840 is a wasteful number, since it uses less digits than its factorization.

1279975497840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4619 (or 4601 counting only the distinct ones).

The product of its (nonzero) digits is 320060160, while the sum is 72.

The spelling of 1279975497840 in words is "one trillion, two hundred seventy-nine billion, nine hundred seventy-five million, four hundred ninety-seven thousand, eight hundred forty".