512140021 has 4 divisors (see below), whose sum is σ = 513146700. Its totient is φ = 511133344.

The previous prime is 512139997. The next prime is 512140033. The reversal of 512140021 is 120041215.

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 338928100 + 173211921 = 18410^2 + 13161^2 .

It is a cyclic number.

It is not a de Polignac number, because 512140021 - 2⁵ = 512139989 is a prime.

It is a super-2 number, since 2×512140021² = 524574802219760882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 512139977 and 512140004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (512140121) 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, 502576 + ... + 503593.

It is an arithmetic number, because the mean of its divisors is an integer number (128286675).

Almost surely, 2^512140021 is an apocalyptic number.

It is an amenable number.

512140021 is a deficient number, since it is larger than the sum of its proper divisors (1006679).

512140021 is a wasteful number, since it uses less digits than its factorization.

512140021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1006678.

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 512140021 is about 22630.5108426655. The cubic root of 512140021 is about 800.0729209571.

Adding to 512140021 its reverse (120041215), we get a palindrome (632181236).

The spelling of 512140021 in words is "five hundred twelve million, one hundred forty thousand, twenty-one".