21276323437 has 2 divisors, whose sum is σ = 21276323438. Its totient is φ = 21276323436.

The previous prime is 21276323413. The next prime is 21276323449. The reversal of 21276323437 is 73432367212.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12023999716 + 9252323721 = 109654^2 + 96189^2 .

It is a cyclic number.

It is not a de Polignac number, because 21276323437 - 2¹⁵ = 21276290669 is a prime.

It is a super-3 number, since 3×21276323437³ (a number of 32 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21276323437.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21276383437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10638161718 + 10638161719.

It is an arithmetic number, because the mean of its divisors is an integer number (10638161719).

Almost surely, 2^21276323437 is an apocalyptic number.

It is an amenable number.

21276323437 is a deficient number, since it is larger than the sum of its proper divisors (1).

21276323437 is an equidigital number, since it uses as much as digits as its factorization.

21276323437 is an evil number, because the sum of its binary digits is even.

The product of its digits is 254016, while the sum is 40.

The spelling of 21276323437 in words is "twenty-one billion, two hundred seventy-six million, three hundred twenty-three thousand, four hundred thirty-seven".