11720011081 has 9 divisors (see below), whose sum is σ = 11890776519. Its totient is φ = 11551668336.

The previous prime is 11720011067. The next prime is 11720011087. The reversal of 11720011081 is 18011002711.

The square root of 11720011081 is 108259.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 6652849225 + 5067161856 = 81565^2 + 71184^2 .

It is not a de Polignac number, because 11720011081 - 2¹⁷ = 11719880009 is a prime.

It is a super-3 number, since 3×11720011081³ (a number of 31 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11720011087) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 7902166 + ... + 7903648.

It is an arithmetic number, because the mean of its divisors is an integer number (1321197391).

Almost surely, 2^11720011081 is an apocalyptic number.

11720011081 is the 108259-th square number.

11720011081 is the 54130-th centered octagonal number.

It is an amenable number.

11720011081 is a deficient number, since it is larger than the sum of its proper divisors (170765438).

11720011081 is an frugal number, since it uses more digits than its factorization.

11720011081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3112 (or 1556 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 22.

Adding to 11720011081 its reverse (18011002711), we get a palindrome (29731013792).

The spelling of 11720011081 in words is "eleven billion, seven hundred twenty million, eleven thousand, eighty-one".