1221010020240 has 80 divisors (see below), whose sum is σ = 3797224366848. Its totient is φ = 324562387968.

The previous prime is 1221010020203. The next prime is 1221010020271. The reversal of 1221010020240 is 420200101221.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8051944 + ... + 8202183.

Almost surely, 2^{1221010020240} is an apocalyptic number.

1221010020240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221010020240 is an abundant number, since it is smaller than the sum of its proper divisors (2576214346608).

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

1221010020240 is a wasteful number, since it uses less digits than its factorization.

1221010020240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16254456 (or 16254450 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 1221010020240 its reverse (420200101221), we get a palindrome (1641210121461).

The spelling of 1221010020240 in words is "one trillion, two hundred twenty-one billion, ten million, twenty thousand, two hundred forty".