1021210021 has 8 divisors (see below), whose sum is σ = 1100058624. Its totient is φ = 942403440.

The previous prime is 1021210013. The next prime is 1021210037. The reversal of 1021210021 is 1200121201.

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

It is a cyclic number.

It is not a de Polignac number, because 1021210021 - 2³ = 1021210013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021210921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55260 + ... + 71386.

It is an arithmetic number, because the mean of its divisors is an integer number (137507328).

Almost surely, 2^1021210021 is an apocalyptic number.

It is an amenable number.

1021210021 is a deficient number, since it is larger than the sum of its proper divisors (78848603).

1021210021 is a wasteful number, since it uses less digits than its factorization.

1021210021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21011.

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 1021210021 is about 31956.3768440667. The cubic root of 1021210021 is about 1007.0206027906.

Adding to 1021210021 its reverse (1200121201), we get a palindrome (2221331222).

The spelling of 1021210021 in words is "one billion, twenty-one million, two hundred ten thousand, twenty-one".