1228648621 has 2 divisors, whose sum is σ = 1228648622. Its totient is φ = 1228648620.

The previous prime is 1228648609. The next prime is 1228648693. The reversal of 1228648621 is 1268468221.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1187560521 + 41088100 = 34461^2 + 6410^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1228648621 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1228648601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 614324310 + 614324311.

It is an arithmetic number, because the mean of its divisors is an integer number (614324311).

Almost surely, 2^1228648621 is an apocalyptic number.

It is an amenable number.

1228648621 is a deficient number, since it is larger than the sum of its proper divisors (1).

1228648621 is an equidigital number, since it uses as much as digits as its factorization.

1228648621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 73728, while the sum is 40.

The square root of 1228648621 is about 35052.0844030708. The cubic root of 1228648621 is about 1071.0487347790.

The spelling of 1228648621 in words is "one billion, two hundred twenty-eight million, six hundred forty-eight thousand, six hundred twenty-one".