1012040021 has 8 divisors (see below), whose sum is σ = 1040243160. Its totient is φ = 983881728.

The previous prime is 1012039991. The next prime is 1012040047. The reversal of 1012040021 is 1200402101.

It can be written as a sum of positive squares in 4 ways, for example, as 951043921 + 60996100 = 30839^2 + 7810^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1012040021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1012039984 and 1012040011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1012040621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37445 + ... + 58533.

It is an arithmetic number, because the mean of its divisors is an integer number (130030395).

Almost surely, 2^1012040021 is an apocalyptic number.

It is an amenable number.

1012040021 is a deficient number, since it is larger than the sum of its proper divisors (28203139).

1012040021 is a wasteful number, since it uses less digits than its factorization.

1012040021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22423.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 1012040021 is about 31812.5764596331. The cubic root of 1012040021 is about 1003.9973403129.

Adding to 1012040021 its reverse (1200402101), we get a palindrome (2212442122).

The spelling of 1012040021 in words is "one billion, twelve million, forty thousand, twenty-one".