1210030021 has 4 divisors (see below), whose sum is σ = 1210108000. Its totient is φ = 1209952044.

The previous prime is 1210030001. The next prime is 1210030039. The reversal of 1210030021 is 1200300121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1210030021 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 (1210030001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6921 + ... + 49678.

It is an arithmetic number, because the mean of its divisors is an integer number (302527000).

Almost surely, 2^1210030021 is an apocalyptic number.

It is an amenable number.

1210030021 is a deficient number, since it is larger than the sum of its proper divisors (77979).

1210030021 is an equidigital number, since it uses as much as digits as its factorization.

1210030021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77978.

The product of its (nonzero) digits is 12, while the sum is 10.

The square root of 1210030021 is about 34785.4857807103. The cubic root of 1210030021 is about 1065.6110494884.

Adding to 1210030021 its reverse (1200300121), we get a palindrome (2410330142).

The spelling of 1210030021 in words is "one billion, two hundred ten million, thirty thousand, twenty-one".