1221000640804 has 48 divisors (see below), whose sum is σ = 2476616518656. Its totient is φ = 515869754400.

The previous prime is 1221000640789. The next prime is 1221000640807. The reversal of 1221000640804 is 4080460001221.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is not an unprimeable number, because it can be changed into a prime (1221000640807) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31253707 + ... + 31292749.

It is an arithmetic number, because the mean of its divisors is an integer number (51596177472).

Almost surely, 2^{1221000640804} is an apocalyptic number.

1221000640804 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

1221000640804 is an abundant number, since it is smaller than the sum of its proper divisors (1255615877852).

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

1221000640804 is a wasteful number, since it uses less digits than its factorization.

1221000640804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54856 (or 54854 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 28.

The spelling of 1221000640804 in words is "one trillion, two hundred twenty-one billion, six hundred forty thousand, eight hundred four".