21278361537031 has 2 divisors, whose sum is σ = 21278361537032. Its totient is φ = 21278361537030.

The previous prime is 21278361536981. The next prime is 21278361537067. The reversal of 21278361537031 is 13073516387212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21278361537031 - 2⁴³ = 12482268514823 is a prime.

It is a super-2 number, since 2×21278361537031² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21278361537731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10639180768515 + 10639180768516.

It is an arithmetic number, because the mean of its divisors is an integer number (10639180768516).

Almost surely, 2^{21278361537031} is an apocalyptic number.

21278361537031 is a deficient number, since it is larger than the sum of its proper divisors (1).

21278361537031 is an equidigital number, since it uses as much as digits as its factorization.

21278361537031 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1270080, while the sum is 49.

The spelling of 21278361537031 in words is "twenty-one trillion, two hundred seventy-eight billion, three hundred sixty-one million, five hundred thirty-seven thousand, thirty-one".