1221487733 has 2 divisors, whose sum is σ = 1221487734. Its totient is φ = 1221487732.

The previous prime is 1221487727. The next prime is 1221487759. The reversal of 1221487733 is 3377841221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 628906084 + 592581649 = 25078^2 + 24343^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221487733 - 2⁶ = 1221487669 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221487783) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610743866 + 610743867.

It is an arithmetic number, because the mean of its divisors is an integer number (610743867).

Almost surely, 2^1221487733 is an apocalyptic number.

It is an amenable number.

1221487733 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221487733 is an equidigital number, since it uses as much as digits as its factorization.

1221487733 is an evil number, because the sum of its binary digits is even.

The product of its digits is 56448, while the sum is 38.

The square root of 1221487733 is about 34949.7887404202. The cubic root of 1221487733 is about 1068.9638944099.

The spelling of 1221487733 in words is "one billion, two hundred twenty-one million, four hundred eighty-seven thousand, seven hundred thirty-three".