11372820821 has 2 divisors, whose sum is σ = 11372820822. Its totient is φ = 11372820820.

The previous prime is 11372820799. The next prime is 11372820853. The reversal of 11372820821 is 12802827311.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10317480625 + 1055340196 = 101575^2 + 32486^2 .

It is a cyclic number.

It is not a de Polignac number, because 11372820821 - 2¹⁸ = 11372558677 is a prime.

It is a super-2 number, since 2×11372820821² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11372820881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5686410410 + 5686410411.

It is an arithmetic number, because the mean of its divisors is an integer number (5686410411).

Almost surely, 2^11372820821 is an apocalyptic number.

It is an amenable number.

11372820821 is a deficient number, since it is larger than the sum of its proper divisors (1).

11372820821 is an equidigital number, since it uses as much as digits as its factorization.

11372820821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10752, while the sum is 35.

The spelling of 11372820821 in words is "eleven billion, three hundred seventy-two million, eight hundred twenty thousand, eight hundred twenty-one".