1221427508 has 36 divisors (see below), whose sum is σ = 2493781920. Its totient is φ = 521931312.

The previous prime is 1221427507. The next prime is 1221427511. The reversal of 1221427508 is 8057241221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221427507) 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, 59033 + ... + 76991.

It is an arithmetic number, because the mean of its divisors is an integer number (69271720).

Almost surely, 2^1221427508 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221427508, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1246890960).

1221427508 is an abundant number, since it is smaller than the sum of its proper divisors (1272354412).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221427508 is a wasteful number, since it uses less digits than its factorization.

1221427508 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18324 (or 18315 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 32.

The square root of 1221427508 is about 34948.9271366089. The cubic root of 1221427508 is about 1068.9463258316.

Adding to 1221427508 its reverse (8057241221), we get a palindrome (9278668729).

The spelling of 1221427508 in words is "one billion, two hundred twenty-one million, four hundred twenty-seven thousand, five hundred eight".