1221000131 has 16 divisors (see below), whose sum is σ = 1390464768. Its totient is φ = 1064102400.

The previous prime is 1221000127. The next prime is 1221000133. The reversal of 1221000131 is 1310001221.

It is a cyclic number.

It is not a de Polignac number, because 1221000131 - 2² = 1221000127 is a prime.

It is a super-2 number, since 2×1221000131² = 2981682639804034322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221000133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20426 + ... + 53471.

It is an arithmetic number, because the mean of its divisors is an integer number (86904048).

Almost surely, 2^1221000131 is an apocalyptic number.

1221000131 is a deficient number, since it is larger than the sum of its proper divisors (169464637).

1221000131 is a wasteful number, since it uses less digits than its factorization.

1221000131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73982.

The product of its (nonzero) digits is 12, while the sum is 11.

The square root of 1221000131 is about 34942.8122938037. The cubic root of 1221000131 is about 1068.8216366560.

Adding to 1221000131 its reverse (1310001221), we get a palindrome (2531001352).

The spelling of 1221000131 in words is "one billion, two hundred twenty-one million, one hundred thirty-one", and thus it is an aban number.