6502256021 has 4 divisors (see below), whose sum is σ = 6608850444. Its totient is φ = 6395661600.

The previous prime is 6502255993. The next prime is 6502256023. The reversal of 6502256021 is 1206522056.

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 1276990225 + 5225265796 = 35735^2 + 72286^2 .

It is a cyclic number.

It is not a de Polignac number, because 6502256021 - 2²⁶ = 6435147157 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6502256023) 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, 53297120 + ... + 53297241.

It is an arithmetic number, because the mean of its divisors is an integer number (1652212611).

Almost surely, 2^6502256021 is an apocalyptic number.

6502256021 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

It is an amenable number.

6502256021 is a deficient number, since it is larger than the sum of its proper divisors (106594423).

6502256021 is a wasteful number, since it uses less digits than its factorization.

6502256021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106594422.

The product of its (nonzero) digits is 7200, while the sum is 29.

The square root of 6502256021 is about 80636.5675174731. The cubic root of 6502256021 is about 1866.4714668581.

Adding to 6502256021 its reverse (1206522056), we get a palindrome (7708778077).

The spelling of 6502256021 in words is "six billion, five hundred two million, two hundred fifty-six thousand, twenty-one".