1220400513 has 20 divisors (see below), whose sum is σ = 1824717268. Its totient is φ = 812864160.

The previous prime is 1220400499. The next prime is 1220400551. The reversal of 1220400513 is 3150040221.

It can be written as a sum of positive squares in 2 ways, for example, as 624650049 + 595750464 = 24993^2 + 24408^2 .

It is not a de Polignac number, because 1220400513 - 2¹⁴ = 1220384129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1220400413) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 92043 + ... + 104463.

Almost surely, 2^1220400513 is an apocalyptic number.

It is an amenable number.

1220400513 is a deficient number, since it is larger than the sum of its proper divisors (604316755).

1220400513 is a wasteful number, since it uses less digits than its factorization.

1220400513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13646 (or 13637 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 1220400513 is about 34934.2312495924. The cubic root of 1220400513 is about 1068.6466463305.

Adding to 1220400513 its reverse (3150040221), we get a palindrome (4370440734).

The spelling of 1220400513 in words is "one billion, two hundred twenty million, four hundred thousand, five hundred thirteen".