1221064542208 has 96 divisors (see below), whose sum is σ = 2865738657600. Its totient is φ = 509169549312.

The previous prime is 1221064542193. The next prime is 1221064542209. The reversal of 1221064542208 is 8022454601221.

It is a super-2 number, since 2×1221064542208² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is not an unprimeable number, because it can be changed into a prime (1221064542209) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 620578 + ... + 1681441.

It is an arithmetic number, because the mean of its divisors is an integer number (29851444350).

Almost surely, 2^{1221064542208} is an apocalyptic number.

It is an amenable number.

1221064542208 is an abundant number, since it is smaller than the sum of its proper divisors (1644674115392).

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

1221064542208 is an equidigital number, since it uses as much as digits as its factorization.

1221064542208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2302085 (or 2302065 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 37.

The spelling of 1221064542208 in words is "one trillion, two hundred twenty-one billion, sixty-four million, five hundred forty-two thousand, two hundred eight".