11821220072 has 16 divisors (see below), whose sum is σ = 22182840900. Its totient is φ = 5905795840.

The previous prime is 11821220069. The next prime is 11821220077. The reversal of 11821220072 is 27002212811.

It can be written as a sum of positive squares in 2 ways, for example, as 9259443076 + 2561776996 = 96226^2 + 50614^2 .

It is not an unprimeable number, because it can be changed into a prime (11821220077) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 591329 + ... + 610992.

Almost surely, 2^11821220072 is an apocalyptic number.

It is an amenable number.

11821220072 is a deficient number, since it is larger than the sum of its proper divisors (10361620828).

11821220072 is a wasteful number, since it uses less digits than its factorization.

11821220072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1203556 (or 1203552 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 26.

Adding to 11821220072 its reverse (27002212811), we get a palindrome (38823432883).

The spelling of 11821220072 in words is "eleven billion, eight hundred twenty-one million, two hundred twenty thousand, seventy-two".