1288016621 has 2 divisors, whose sum is σ = 1288016622. Its totient is φ = 1288016620.

The previous prime is 1288016617. The next prime is 1288016641. The reversal of 1288016621 is 1266108821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1121245225 + 166771396 = 33485^2 + 12914^2 .

It is an emirp because it is prime and its reverse (1266108821) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1288016621 - 2² = 1288016617 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1288016641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 644008310 + 644008311.

It is an arithmetic number, because the mean of its divisors is an integer number (644008311).

Almost surely, 2^1288016621 is an apocalyptic number.

It is an amenable number.

1288016621 is a deficient number, since it is larger than the sum of its proper divisors (1).

1288016621 is an equidigital number, since it uses as much as digits as its factorization.

1288016621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9216, while the sum is 35.

The square root of 1288016621 is about 35888.9484521350. The cubic root of 1288016621 is about 1088.0290452008.

The spelling of 1288016621 in words is "one billion, two hundred eighty-eight million, sixteen thousand, six hundred twenty-one".