1221004031 has 4 divisors (see below), whose sum is σ = 1314927432. Its totient is φ = 1127080632.

The previous prime is 1221004019. The next prime is 1221004061. The reversal of 1221004031 is 1304001221.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221004031 is a prime.

It is a super-2 number, since 2×1221004031² = 2981701687436497922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1221003997 and 1221004015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221004061) 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 3 ways as a sum of consecutive naturals, for example, 46961681 + ... + 46961706.

It is an arithmetic number, because the mean of its divisors is an integer number (328731858).

Almost surely, 2^1221004031 is an apocalyptic number.

1221004031 is a deficient number, since it is larger than the sum of its proper divisors (93923401).

1221004031 is an equidigital number, since it uses as much as digits as its factorization.

1221004031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93923400.

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

The square root of 1221004031 is about 34942.8680992273. The cubic root of 1221004031 is about 1068.8227746302.

Adding to 1221004031 its reverse (1304001221), we get a palindrome (2525005252).

The spelling of 1221004031 in words is "one billion, two hundred twenty-one million, four thousand, thirty-one".