20311099973 has 2 divisors, whose sum is σ = 20311099974. Its totient is φ = 20311099972.

The previous prime is 20311099937. The next prime is 20311100021. The reversal of 20311099973 is 37999011302.

Together with previous prime (20311099937) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17874887809 + 2436212164 = 133697^2 + 49358^2 .

It is a cyclic number.

It is not a de Polignac number, because 20311099973 - 2¹⁴ = 20311083589 is a prime.

It is a super-2 number, since 2×20311099973² (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 (20311099903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10155549986 + 10155549987.

It is an arithmetic number, because the mean of its divisors is an integer number (10155549987).

Almost surely, 2^20311099973 is an apocalyptic number.

It is an amenable number.

20311099973 is a deficient number, since it is larger than the sum of its proper divisors (1).

20311099973 is an equidigital number, since it uses as much as digits as its factorization.

20311099973 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 91854, while the sum is 44.

The spelling of 20311099973 in words is "twenty billion, three hundred eleven million, ninety-nine thousand, nine hundred seventy-three".