6455111021 has 4 divisors (see below), whose sum is σ = 6834823452. Its totient is φ = 6075398592.

The previous prime is 6455111011. The next prime is 6455111071. The reversal of 6455111021 is 1201115546.

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 4686908521 + 1768202500 = 68461^2 + 42050^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6455111021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6455111011) 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, 189856190 + ... + 189856223.

It is an arithmetic number, because the mean of its divisors is an integer number (1708705863).

Almost surely, 2^6455111021 is an apocalyptic number.

It is an amenable number.

6455111021 is a deficient number, since it is larger than the sum of its proper divisors (379712431).

6455111021 is a wasteful number, since it uses less digits than its factorization.

6455111021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 379712430.

The product of its (nonzero) digits is 1200, while the sum is 26.

The square root of 6455111021 is about 80343.7055468566. The cubic root of 6455111021 is about 1861.9495322983.

Adding to 6455111021 its reverse (1201115546), we get a palindrome (7656226567).

The spelling of 6455111021 in words is "six billion, four hundred fifty-five million, one hundred eleven thousand, twenty-one".