663020251 has 4 divisors (see below), whose sum is σ = 666852912. Its totient is φ = 659187592.

The previous prime is 663020249. The next prime is 663020261. The reversal of 663020251 is 152020366.

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

It is a cyclic number.

It is not a de Polignac number, because 663020251 - 2¹ = 663020249 is a prime.

It is a super-2 number, since 2×663020251² = 879191706472206002, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (663020221) 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, 1916071 + ... + 1916416.

It is an arithmetic number, because the mean of its divisors is an integer number (166713228).

Almost surely, 2^663020251 is an apocalyptic number.

663020251 is a deficient number, since it is larger than the sum of its proper divisors (3832661).

663020251 is a wasteful number, since it uses less digits than its factorization.

663020251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3832660.

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 663020251 is about 25749.1796179995. The cubic root of 663020251 is about 871.9848332765.

The spelling of 663020251 in words is "six hundred sixty-three million, twenty thousand, two hundred fifty-one".