1655511015561 has 48 divisors (see below), whose sum is σ = 2495630180736. Its totient is φ = 973894192128.

The previous prime is 1655511015553. The next prime is 1655511015569. The reversal of 1655511015561 is 1655101155561.

It is an interprime number because it is at equal distance from previous prime (1655511015553) and next prime (1655511015569).

It is not a de Polignac number, because 1655511015561 - 2³ = 1655511015553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1655511015569) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 19700145 + ... + 19784001.

It is an arithmetic number, because the mean of its divisors is an integer number (51992295432).

Almost surely, 2^{1655511015561} is an apocalyptic number.

It is an amenable number.

1655511015561 is a deficient number, since it is larger than the sum of its proper divisors (840119165175).

1655511015561 is a wasteful number, since it uses less digits than its factorization.

1655511015561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85602 (or 85589 counting only the distinct ones).

The product of its (nonzero) digits is 112500, while the sum is 42.

The spelling of 1655511015561 in words is "one trillion, six hundred fifty-five billion, five hundred eleven million, fifteen thousand, five hundred sixty-one".