1221988347 has 12 divisors (see below), whose sum is σ = 1766300640. Its totient is φ = 814102128.

The previous prime is 1221988291. The next prime is 1221988357. The reversal of 1221988347 is 7438891221.

It is a happy number.

1221988347 is a `hidden beast` number, since 1 + 221 + 9 + 88 + 347 = 666.

It is not a de Polignac number, because 1221988347 - 2¹⁰ = 1221987323 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (1221988357) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 32272 + ... + 59037.

It is an arithmetic number, because the mean of its divisors is an integer number (147191720).

Almost surely, 2^1221988347 is an apocalyptic number.

1221988347 is a deficient number, since it is larger than the sum of its proper divisors (544312293).

1221988347 is a wasteful number, since it uses less digits than its factorization.

1221988347 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92802 (or 92799 counting only the distinct ones).

The product of its digits is 193536, while the sum is 45.

The square root of 1221988347 is about 34956.9499098534. The cubic root of 1221988347 is about 1069.1099090297.

The spelling of 1221988347 in words is "one billion, two hundred twenty-one million, nine hundred eighty-eight thousand, three hundred forty-seven".