1221004013 has 16 divisors (see below), whose sum is σ = 1293580800. Its totient is φ = 1150131840.

The previous prime is 1221004009. The next prime is 1221004019. The reversal of 1221004013 is 3104001221.

It is a cyclic number.

It is not a de Polignac number, because 1221004013 - 2² = 1221004009 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221004019) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1033283 + ... + 1034463.

It is an arithmetic number, because the mean of its divisors is an integer number (80848800).

Almost surely, 2^1221004013 is an apocalyptic number.

It is an amenable number.

1221004013 is a deficient number, since it is larger than the sum of its proper divisors (72576787).

1221004013 is a wasteful number, since it uses less digits than its factorization.

1221004013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1852.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 1221004013 is about 34942.8678416641. The cubic root of 1221004013 is about 1068.8227693780.

Adding to 1221004013 its reverse (3104001221), we get a palindrome (4325005234).

The spelling of 1221004013 in words is "one billion, two hundred twenty-one million, four thousand, thirteen".