1221528802 has 16 divisors (see below), whose sum is σ = 2006686080. Its totient is φ = 554226192.

The previous prime is 1221528793. The next prime is 1221528811. The reversal of 1221528802 is 2088251221.

It is an interprime number because it is at equal distance from previous prime (1221528793) and next prime (1221528811).

It is a super-2 number, since 2×1221528802² = 2984265228231110408, which contains 22 as substring.

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, 396618 + ... + 399685.

It is an arithmetic number, because the mean of its divisors is an integer number (125417880).

Almost surely, 2^1221528802 is an apocalyptic number.

1221528802 is a deficient number, since it is larger than the sum of its proper divisors (785157278).

1221528802 is a wasteful number, since it uses less digits than its factorization.

1221528802 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 796377.

The product of its (nonzero) digits is 5120, while the sum is 31.

The square root of 1221528802 is about 34950.3762783750. The cubic root of 1221528802 is about 1068.9758745510.

The spelling of 1221528802 in words is "one billion, two hundred twenty-one million, five hundred twenty-eight thousand, eight hundred two".