21272120497 has 2 divisors, whose sum is σ = 21272120498. Its totient is φ = 21272120496.

The previous prime is 21272120449. The next prime is 21272120509. The reversal of 21272120497 is 79402127212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20604879936 + 667240561 = 143544^2 + 25831^2 .

It is a cyclic number.

It is not a de Polignac number, because 21272120497 - 2¹⁵ = 21272087729 is a prime.

It is a super-2 number, since 2×21272120497² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21272120437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10636060248 + 10636060249.

It is an arithmetic number, because the mean of its divisors is an integer number (10636060249).

Almost surely, 2^21272120497 is an apocalyptic number.

It is an amenable number.

21272120497 is a deficient number, since it is larger than the sum of its proper divisors (1).

21272120497 is an equidigital number, since it uses as much as digits as its factorization.

21272120497 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 28224, while the sum is 37.

The spelling of 21272120497 in words is "twenty-one billion, two hundred seventy-two million, one hundred twenty thousand, four hundred ninety-seven".