1221249039 has 16 divisors (see below), whose sum is σ = 1640466432. Its totient is φ = 808115168.

The previous prime is 1221249031. The next prime is 1221249041. The reversal of 1221249039 is 9309421221.

It is a cyclic number.

It is not a de Polignac number, because 1221249039 - 2³ = 1221249031 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221249031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 384034 + ... + 387200.

It is an arithmetic number, because the mean of its divisors is an integer number (102529152).

Almost surely, 2^1221249039 is an apocalyptic number.

1221249039 is a deficient number, since it is larger than the sum of its proper divisors (419217393).

1221249039 is a wasteful number, since it uses less digits than its factorization.

1221249039 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4086.

The product of its (nonzero) digits is 7776, while the sum is 33.

The square root of 1221249039 is about 34946.3737603775. The cubic root of 1221249039 is about 1068.8942602300.

The spelling of 1221249039 in words is "one billion, two hundred twenty-one million, two hundred forty-nine thousand, thirty-nine".