1220321631 has 16 divisors (see below), whose sum is σ = 1647324000. Its totient is φ = 803455488.

The previous prime is 1220321587. The next prime is 1220321633. The reversal of 1220321631 is 1361230221.

1220321631 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1220321631 - 2⁶ = 1220321567 is a prime.

It is a super-2 number, since 2×1220321631² = 2978369766173000322, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1220321598 and 1220321607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220321633) 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, 277905 + ... + 282261.

It is an arithmetic number, because the mean of its divisors is an integer number (102957750).

Almost surely, 2^1220321631 is an apocalyptic number.

1220321631 is a deficient number, since it is larger than the sum of its proper divisors (427002369).

1220321631 is a wasteful number, since it uses less digits than its factorization.

1220321631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5498.

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 1220321631 is about 34933.1022241083. The cubic root of 1220321631 is about 1068.6236214300.

Adding to 1220321631 its reverse (1361230221), we get a palindrome (2581551852).

The spelling of 1220321631 in words is "one billion, two hundred twenty million, three hundred twenty-one thousand, six hundred thirty-one".