11555771620 has 24 divisors (see below), whose sum is σ = 24279925824. Its totient is φ = 4619869536.

The previous prime is 11555771611. The next prime is 11555771621. The reversal of 11555771620 is 2617755511.

It is not an unprimeable number, because it can be changed into a prime (11555771621) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 113352 + ... + 189631.

It is an arithmetic number, because the mean of its divisors is an integer number (1011663576).

Almost surely, 2^11555771620 is an apocalyptic number.

11555771620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11555771620 is an abundant number, since it is smaller than the sum of its proper divisors (12724154204).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

11555771620 is a wasteful number, since it uses less digits than its factorization.

11555771620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304899 (or 304897 counting only the distinct ones).

The product of its (nonzero) digits is 73500, while the sum is 40.

It can be divided in two parts, 1155 and 5771620, that added together give a palindrome (5772775).

The spelling of 11555771620 in words is "eleven billion, five hundred fifty-five million, seven hundred seventy-one thousand, six hundred twenty".