1011002021 has 4 divisors (see below), whose sum is σ = 1021012044. Its totient is φ = 1000992000.

The previous prime is 1011001987. The next prime is 1011002029. The reversal of 1011002021 is 1202001101.

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 870840100 + 140161921 = 29510^2 + 11839^2 .

It is a cyclic number.

It is not a de Polignac number, because 1011002021 - 2¹⁴ = 1010985637 is a prime.

It is a super-3 number, since 3×1011002021³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011002029) 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, 5004860 + ... + 5005061.

It is an arithmetic number, because the mean of its divisors is an integer number (255253011).

Almost surely, 2^1011002021 is an apocalyptic number.

It is an amenable number.

1011002021 is a deficient number, since it is larger than the sum of its proper divisors (10010023).

1011002021 is a wasteful number, since it uses less digits than its factorization.

1011002021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10010022.

The product of its (nonzero) digits is 4, while the sum is 8.

The square root of 1011002021 is about 31796.2579716545. The cubic root of 1011002021 is about 1003.6539725559.

Adding to 1011002021 its reverse (1202001101), we get a palindrome (2213003122).

The spelling of 1011002021 in words is "one billion, eleven million, two thousand, twenty-one".