1021021992 has 24 divisors (see below), whose sum is σ = 2765268090. Its totient is φ = 340340640.

The previous prime is 1021021979. The next prime is 1021021997. The reversal of 1021021992 is 2991201201.

It can be written as a sum of positive squares in only one way, i.e., 1011621636 + 9400356 = 31806^2 + 3066^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is not an unprimeable number, because it can be changed into a prime (1021021997) 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 5 ways as a sum of consecutive naturals, for example, 7090359 + ... + 7090502.

Almost surely, 2^1021021992 is an apocalyptic number.

1021021992 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1021021992 is an abundant number, since it is smaller than the sum of its proper divisors (1744246098).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1021021992 is a wasteful number, since it uses less digits than its factorization.

1021021992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14180873 (or 14180866 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 27.

The square root of 1021021992 is about 31953.4347449535. The cubic root of 1021021992 is about 1006.9587935332.

The spelling of 1021021992 in words is "one billion, twenty-one million, twenty-one thousand, nine hundred ninety-two".