1042749021 has 4 divisors (see below), whose sum is σ = 1390332032. Its totient is φ = 695166012.

The previous prime is 1042748989. The next prime is 1042749041. The reversal of 1042749021 is 1209472401.

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.

It is not a de Polignac number, because 1042749021 - 2⁵ = 1042748989 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1042749021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1042749041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 173791501 + ... + 173791506.

It is an arithmetic number, because the mean of its divisors is an integer number (347583008).

Almost surely, 2^1042749021 is an apocalyptic number.

It is an amenable number.

1042749021 is a deficient number, since it is larger than the sum of its proper divisors (347583011).

1042749021 is an equidigital number, since it uses as much as digits as its factorization.

1042749021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 347583010.

The product of its (nonzero) digits is 4032, while the sum is 30.

The square root of 1042749021 is about 32291.6246262092. The cubic root of 1042749021 is about 1014.0513096048.

The spelling of 1042749021 in words is "one billion, forty-two million, seven hundred forty-nine thousand, twenty-one".