1221002039 has 2 divisors, whose sum is σ = 1221002040. Its totient is φ = 1221002038.

The previous prime is 1221002023. The next prime is 1221002059. The reversal of 1221002039 is 9302001221.

It is an a-pointer prime, because the next prime (1221002059) can be obtained adding 1221002039 to its sum of digits (20).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1221002039 - 2⁴ = 1221002023 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1221002039.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221002009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610501019 + 610501020.

It is an arithmetic number, because the mean of its divisors is an integer number (610501020).

Almost surely, 2^1221002039 is an apocalyptic number.

1221002039 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221002039 is an equidigital number, since it uses as much as digits as its factorization.

1221002039 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 1221002039 is about 34942.8395955452. The cubic root of 1221002039 is about 1068.8221933883.

The spelling of 1221002039 in words is "one billion, two hundred twenty-one million, two thousand, thirty-nine".