5000000021 has 4 divisors (see below), whose sum is σ = 5019455532. Its totient is φ = 4980544512.

The previous prime is 4999999937. The next prime is 5000000029. The reversal of 5000000021 is 1200000005.

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 4831779121 + 168220900 = 69511^2 + 12970^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-5000000021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 4999999945 and 5000000008.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5000000029) 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, 9727370 + ... + 9727883.

It is an arithmetic number, because the mean of its divisors is an integer number (1254863883).

Almost surely, 2^5000000021 is an apocalyptic number.

It is an amenable number.

5000000021 is a deficient number, since it is larger than the sum of its proper divisors (19455511).

5000000021 is a wasteful number, since it uses less digits than its factorization.

5000000021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19455510.

The product of its (nonzero) digits is 10, while the sum is 8.

The square root of 5000000021 is about 70710.6782671472. The cubic root of 5000000021 is about 1709.9759490707.

Adding to 5000000021 its reverse (1200000005), we get a palindrome (6200000026).

The spelling of 5000000021 in words is "five billion, twenty-one", and thus it is an aban number and an uban number.