1611279405887 has 4 divisors (see below), whose sum is σ = 1654827497976. Its totient is φ = 1567731313800.

The previous prime is 1611279405877. The next prime is 1611279405929. The reversal of 1611279405887 is 7885049721161.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1611279405887 - 2¹⁸ = 1611279143743 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 (1611279405817) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21774045989 + ... + 21774046062.

It is an arithmetic number, because the mean of its divisors is an integer number (413706874494).

Almost surely, 2^{1611279405887} is an apocalyptic number.

1611279405887 is a deficient number, since it is larger than the sum of its proper divisors (43548092089).

1611279405887 is an equidigital number, since it uses as much as digits as its factorization.

1611279405887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43548092088.

The product of its (nonzero) digits is 6773760, while the sum is 59.

The spelling of 1611279405887 in words is "one trillion, six hundred eleven billion, two hundred seventy-nine million, four hundred five thousand, eight hundred eighty-seven".