1210145021 has 4 divisors (see below), whose sum is σ = 1210357152. Its totient is φ = 1209932892.

The previous prime is 1210145009. The next prime is 1210145033. The reversal of 1210145021 is 1205410121.

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 an emirpimes, since its reverse is a distinct semiprime: 1205410121 = 571 ⋅2111051.

It is an interprime number because it is at equal distance from previous prime (1210145009) and next prime (1210145033).

It is a cyclic number.

It is not a de Polignac number, because 1210145021 - 2¹⁴ = 1210128637 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 (1210145081) 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, 97265 + ... + 108998.

It is an arithmetic number, because the mean of its divisors is an integer number (302589288).

Almost surely, 2^1210145021 is an apocalyptic number.

It is an amenable number.

1210145021 is a deficient number, since it is larger than the sum of its proper divisors (212131).

1210145021 is an equidigital number, since it uses as much as digits as its factorization.

1210145021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212130.

The product of its (nonzero) digits is 80, while the sum is 17.

The square root of 1210145021 is about 34787.1387297087. The cubic root of 1210145021 is about 1065.6448066092.

Adding to 1210145021 its reverse (1205410121), we get a palindrome (2415555142).

The spelling of 1210145021 in words is "one billion, two hundred ten million, one hundred forty-five thousand, twenty-one".