1221210022021 has 8 divisors (see below), whose sum is σ = 1338923736000. Its totient is φ = 1104612078240.

The previous prime is 1221210022009. The next prime is 1221210022051. The reversal of 1221210022021 is 1202200121221.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1221210022021 - 2³¹ = 1219062538373 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221210021986 and 1221210022004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221210022001) 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, 278940256 + ... + 278944633.

It is an arithmetic number, because the mean of its divisors is an integer number (167365467000).

Almost surely, 2^{1221210022021} is an apocalyptic number.

1221210022021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1221210022021 is a deficient number, since it is larger than the sum of its proper divisors (117713713979).

1221210022021 is a wasteful number, since it uses less digits than its factorization.

1221210022021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 557885099.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 1221210022021 its reverse (1202200121221), we get a palindrome (2423410143242).

The spelling of 1221210022021 in words is "one trillion, two hundred twenty-one billion, two hundred ten million, twenty-two thousand, twenty-one".