1561504517401 has 4 divisors (see below), whose sum is σ = 1562490940032. Its totient is φ = 1560518094772.

The previous prime is 1561504517359. The next prime is 1561504517471. The reversal of 1561504517401 is 1047154051651.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1561504517401 - 2¹⁷ = 1561504386329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1561504517471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 493208941 + ... + 493212106.

It is an arithmetic number, because the mean of its divisors is an integer number (390622735008).

Almost surely, 2^{1561504517401} is an apocalyptic number.

It is an amenable number.

1561504517401 is a deficient number, since it is larger than the sum of its proper divisors (986422631).

1561504517401 is an equidigital number, since it uses as much as digits as its factorization.

1561504517401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 986422630.

The product of its (nonzero) digits is 84000, while the sum is 40.

The spelling of 1561504517401 in words is "one trillion, five hundred sixty-one billion, five hundred four million, five hundred seventeen thousand, four hundred one".