1555616611645 has 16 divisors (see below), whose sum is σ = 1889559931392. Its totient is φ = 1229285183040.

The previous prime is 1555616611643. The next prime is 1555616611663. The reversal of 1555616611645 is 5461166165551.

It is not a de Polignac number, because 1555616611645 - 2¹ = 1555616611643 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1555616611592 and 1555616611601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1555616611643) 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, 2079619 + ... + 2726911.

It is an arithmetic number, because the mean of its divisors is an integer number (118097495712).

Almost surely, 2^{1555616611645} is an apocalyptic number.

It is an amenable number.

1555616611645 is a deficient number, since it is larger than the sum of its proper divisors (333943319747).

1555616611645 is an equidigital number, since it uses as much as digits as its factorization.

1555616611645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 653172.

The product of its digits is 3240000, while the sum is 52.

The spelling of 1555616611645 in words is "one trillion, five hundred fifty-five billion, six hundred sixteen million, six hundred eleven thousand, six hundred forty-five".