21225574813 has 2 divisors, whose sum is σ = 21225574814. Its totient is φ = 21225574812.

The previous prime is 21225574801. The next prime is 21225574819. The reversal of 21225574813 is 31847552212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19585162809 + 1640412004 = 139947^2 + 40502^2 .

It is a cyclic number.

It is not a de Polignac number, because 21225574813 - 2²¹ = 21223477661 is a prime.

It is a super-2 number, since 2×21225574813² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21225574819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10612787406 + 10612787407.

It is an arithmetic number, because the mean of its divisors is an integer number (10612787407).

Almost surely, 2^21225574813 is an apocalyptic number.

It is an amenable number.

21225574813 is a deficient number, since it is larger than the sum of its proper divisors (1).

21225574813 is an equidigital number, since it uses as much as digits as its factorization.

21225574813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 134400, while the sum is 40.

It can be divided in two parts, 212255748 and 13, that added together give a square (212255761 = 14569²).

The spelling of 21225574813 in words is "twenty-one billion, two hundred twenty-five million, five hundred seventy-four thousand, eight hundred thirteen".