1221401204 has 12 divisors (see below), whose sum is σ = 2142391524. Its totient is φ = 609289344.

The previous prime is 1221401189. The next prime is 1221401219. The reversal of 1221401204 is 4021041221.

It is an interprime number because it is at equal distance from previous prime (1221401189) and next prime (1221401219).

It can be written as a sum of positive squares in 2 ways, for example, as 623500900 + 597900304 = 24970^2 + 24452^2 .

It is a super-2 number, since 2×1221401204² = 2983641802265299232, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 350867 + ... + 354330.

It is an arithmetic number, because the mean of its divisors is an integer number (178532627).

Almost surely, 2^1221401204 is an apocalyptic number.

It is an amenable number.

1221401204 is a deficient number, since it is larger than the sum of its proper divisors (920990320).

1221401204 is a wasteful number, since it uses less digits than its factorization.

1221401204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 705634 (or 705632 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 1221401204 is about 34948.5508140180. The cubic root of 1221401204 is about 1068.9386523605.

Adding to 1221401204 its reverse (4021041221), we get a palindrome (5242442425).

The spelling of 1221401204 in words is "one billion, two hundred twenty-one million, four hundred one thousand, two hundred four".