1210101021 has 48 divisors (see below), whose sum is σ = 1912882608. Its totient is φ = 734054400.

The previous prime is 1210101007. The next prime is 1210101031. The reversal of 1210101021 is 1201010121.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 93605625 + 1116495396 = 9675^2 + 33414^2 .

It is not a de Polignac number, because 1210101021 - 2⁵ = 1210100989 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 1210100994 and 1210101012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1210101031) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1024051 + ... + 1025231.

It is an arithmetic number, because the mean of its divisors is an integer number (39851721).

Almost surely, 2^1210101021 is an apocalyptic number.

It is an amenable number.

1210101021 is a deficient number, since it is larger than the sum of its proper divisors (702781587).

1210101021 is a wasteful number, since it uses less digits than its factorization.

1210101021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1422 (or 1419 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

The square root of 1210101021 is about 34786.5063063252. The cubic root of 1210101021 is about 1065.6318910939.

Adding to 1210101021 its reverse (1201010121), we get a palindrome (2411111142).

The spelling of 1210101021 in words is "one billion, two hundred ten million, one hundred one thousand, twenty-one".