1020557021 has 4 divisors (see below), whose sum is σ = 1113334944. Its totient is φ = 927779100.

The previous prime is 1020557011. The next prime is 1020557033. The reversal of 1020557021 is 1207550201.

It is a happy number.

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 a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1020557021 is a prime.

It is a super-2 number, since 2×1020557021² = 2083073266224788882, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1020557011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46388945 + ... + 46388966.

It is an arithmetic number, because the mean of its divisors is an integer number (278333736).

Almost surely, 2^1020557021 is an apocalyptic number.

1020557021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1020557021 is a deficient number, since it is larger than the sum of its proper divisors (92777923).

1020557021 is an equidigital number, since it uses as much as digits as its factorization.

1020557021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92777922.

The product of its (nonzero) digits is 700, while the sum is 23.

The square root of 1020557021 is about 31946.1581571243. The cubic root of 1020557021 is about 1006.8059147730.

The spelling of 1020557021 in words is "one billion, twenty million, five hundred fifty-seven thousand, twenty-one".