320949945551 has 4 divisors (see below), whose sum is σ = 321209405112. Its totient is φ = 320690485992.

The previous prime is 320949945541. The next prime is 320949945583. The reversal of 320949945551 is 155549949023.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-320949945551 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 (320949945521) 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, 129727925 + ... + 129730398.

It is an arithmetic number, because the mean of its divisors is an integer number (80302351278).

Almost surely, 2^320949945551 is an apocalyptic number.

320949945551 is a deficient number, since it is larger than the sum of its proper divisors (259459561).

320949945551 is a wasteful number, since it uses less digits than its factorization.

320949945551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 259459560.

The product of its (nonzero) digits is 8748000, while the sum is 56.

The spelling of 320949945551 in words is "three hundred twenty billion, nine hundred forty-nine million, nine hundred forty-five thousand, five hundred fifty-one".