1284942521 has 4 divisors (see below), whose sum is σ = 1285184292. Its totient is φ = 1284700752.

The previous prime is 1284942511. The next prime is 1284942553. The reversal of 1284942521 is 1252494821.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 748788496 + 536154025 = 27364^2 + 23155^2 .

It is a cyclic number.

It is not a de Polignac number, because 1284942521 - 2⁶ = 1284942457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1284942511) 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, 112730 + ... + 123603.

It is an arithmetic number, because the mean of its divisors is an integer number (321296073).

Almost surely, 2^1284942521 is an apocalyptic number.

It is an amenable number.

1284942521 is a deficient number, since it is larger than the sum of its proper divisors (241771).

1284942521 is an equidigital number, since it uses as much as digits as its factorization.

1284942521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241770.

The product of its digits is 46080, while the sum is 38.

The square root of 1284942521 is about 35846.0949198096. The cubic root of 1284942521 is about 1087.1627586175.

The spelling of 1284942521 in words is "one billion, two hundred eighty-four million, nine hundred forty-two thousand, five hundred twenty-one".