12640214621 has 2 divisors, whose sum is σ = 12640214622. Its totient is φ = 12640214620.

The previous prime is 12640214591. The next prime is 12640214677. The reversal of 12640214621 is 12641204621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11037813721 + 1602400900 = 105061^2 + 40030^2 .

It is a cyclic number.

It is not a de Polignac number, because 12640214621 - 2⁶ = 12640214557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12640210621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6320107310 + 6320107311.

It is an arithmetic number, because the mean of its divisors is an integer number (6320107311).

Almost surely, 2^12640214621 is an apocalyptic number.

It is an amenable number.

12640214621 is a deficient number, since it is larger than the sum of its proper divisors (1).

12640214621 is an equidigital number, since it uses as much as digits as its factorization.

12640214621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4608, while the sum is 29.

The spelling of 12640214621 in words is "twelve billion, six hundred forty million, two hundred fourteen thousand, six hundred twenty-one".