1221617876 has 12 divisors (see below), whose sum is σ = 2141938260. Its totient is φ = 609635520.

The previous prime is 1221617867. The next prime is 1221617879. The reversal of 1221617876 is 6787161221.

It can be written as a sum of positive squares in 2 ways, for example, as 395055376 + 826562500 = 19876^2 + 28750^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221617879) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 291011 + ... + 295178.

It is an arithmetic number, because the mean of its divisors is an integer number (178494855).

Almost surely, 2^1221617876 is an apocalyptic number.

It is an amenable number.

1221617876 is a deficient number, since it is larger than the sum of its proper divisors (920320384).

1221617876 is a wasteful number, since it uses less digits than its factorization.

1221617876 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 586714 (or 586712 counting only the distinct ones).

The product of its digits is 56448, while the sum is 41.

The square root of 1221617876 is about 34951.6505475779. The cubic root of 1221617876 is about 1069.0018571947.

The spelling of 1221617876 in words is "one billion, two hundred twenty-one million, six hundred seventeen thousand, eight hundred seventy-six".