1221000912840 has 32 divisors (see below), whose sum is σ = 3663002738880. Its totient is φ = 325600243392.

The previous prime is 1221000912811. The next prime is 1221000912889. The reversal of 1221000912840 is 482190001221.

It is a happy number.

It is a super-2 number, since 2×1221000912840² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 1221000912798 and 1221000912807.

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, 5087503684 + ... + 5087503923.

It is an arithmetic number, because the mean of its divisors is an integer number (114468835590).

Almost surely, 2^{1221000912840} is an apocalyptic number.

1221000912840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221000912840 is an abundant number, since it is smaller than the sum of its proper divisors (2442001826040).

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

1221000912840 is a wasteful number, since it uses less digits than its factorization.

1221000912840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10175007621 (or 10175007617 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 30.

The spelling of 1221000912840 in words is "one trillion, two hundred twenty-one billion, nine hundred twelve thousand, eight hundred forty".