1551005106561 has 24 divisors (see below), whose sum is σ = 2317994251560. Its totient is φ = 998175628800.

The previous prime is 1551005106533. The next prime is 1551005106569. The reversal of 1551005106561 is 1656015001551.

It is a happy number.

1551005106561 is a `hidden beast` number, since 1 + 551 + 0 + 0 + 51 + 0 + 6 + 56 + 1 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 255915586161 + 1295089520400 = 505881^2 + 1138020^2 .

It is not a de Polignac number, because 1551005106561 - 2¹³ = 1551005098369 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1551005106569) 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 23 ways as a sum of consecutive naturals, for example, 1008841 + ... + 2029721.

It is an arithmetic number, because the mean of its divisors is an integer number (96583093815).

Almost surely, 2^{1551005106561} is an apocalyptic number.

It is an amenable number.

1551005106561 is a deficient number, since it is larger than the sum of its proper divisors (766989144999).

1551005106561 is a wasteful number, since it uses less digits than its factorization.

1551005106561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1026737 (or 1026734 counting only the distinct ones).

The product of its (nonzero) digits is 22500, while the sum is 36.

The spelling of 1551005106561 in words is "one trillion, five hundred fifty-one billion, five million, one hundred six thousand, five hundred sixty-one".