1221012013 has 16 divisors (see below), whose sum is σ = 1345833216. Its totient is φ = 1100710080.

The previous prime is 1221012007. The next prime is 1221012049. The reversal of 1221012013 is 3102101221.

It is a cyclic number.

It is not a de Polignac number, because 1221012013 - 2⁹ = 1221011501 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a junction number, because it is equal to n+sod(n) for n = 1221011984 and 1221012002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221012073) 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, 317643 + ... + 321463.

It is an arithmetic number, because the mean of its divisors is an integer number (84114576).

Almost surely, 2^1221012013 is an apocalyptic number.

1221012013 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1221012013 is a deficient number, since it is larger than the sum of its proper divisors (124821203).

1221012013 is a wasteful number, since it uses less digits than its factorization.

1221012013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4404.

The product of its (nonzero) digits is 24, while the sum is 13.

The square root of 1221012013 is about 34942.9823140498. The cubic root of 1221012013 is about 1068.8251036765.

Adding to 1221012013 its reverse (3102101221), we get a palindrome (4323113234).

The spelling of 1221012013 in words is "one billion, two hundred twenty-one million, twelve thousand, thirteen".