1221167528 has 32 divisors (see below), whose sum is σ = 2770718400. Its totient is φ = 492571392.

The previous prime is 1221167503. The next prime is 1221167551. The reversal of 1221167528 is 8257611221.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 640418 + ... + 642321.

It is an arithmetic number, because the mean of its divisors is an integer number (86584950).

Almost surely, 2^1221167528 is an apocalyptic number.

It is an amenable number.

1221167528 is an abundant number, since it is smaller than the sum of its proper divisors (1549550872).

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

1221167528 is a wasteful number, since it uses less digits than its factorization.

1221167528 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1282769 (or 1282765 counting only the distinct ones).

The product of its digits is 13440, while the sum is 35.

The square root of 1221167528 is about 34945.2075111881. The cubic root of 1221167528 is about 1068.8704789548.

Adding to 1221167528 its reverse (8257611221), we get a palindrome (9478778749).

The spelling of 1221167528 in words is "one billion, two hundred twenty-one million, one hundred sixty-seven thousand, five hundred twenty-eight".