21437550073931 has 2 divisors, whose sum is σ = 21437550073932. Its totient is φ = 21437550073930.

The previous prime is 21437550073909. The next prime is 21437550073949. The reversal of 21437550073931 is 13937005573412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21437550073931 - 2¹⁸ = 21437549811787 is a prime.

It is a super-2 number, since 2×21437550073931² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21437550073931.

It is not a weakly prime, because it can be changed into another prime (21437550070931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10718775036965 + 10718775036966.

It is an arithmetic number, because the mean of its divisors is an integer number (10718775036966).

Almost surely, 2^{21437550073931} is an apocalyptic number.

21437550073931 is a deficient number, since it is larger than the sum of its proper divisors (1).

21437550073931 is an equidigital number, since it uses as much as digits as its factorization.

21437550073931 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2381400, while the sum is 50.

The spelling of 21437550073931 in words is "twenty-one trillion, four hundred thirty-seven billion, five hundred fifty million, seventy-three thousand, nine hundred thirty-one".