664662551 has 4 divisors (see below), whose sum is σ = 759614352. Its totient is φ = 569710752.

The previous prime is 664662547. The next prime is 664662569. The reversal of 664662551 is 155266466.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 155266466 = 2 ⋅77633233.

It is a cyclic number.

It is not a de Polignac number, because 664662551 - 2² = 664662547 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 664662499 and 664662508.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664664551) 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, 47475890 + ... + 47475903.

It is an arithmetic number, because the mean of its divisors is an integer number (189903588).

Almost surely, 2^664662551 is an apocalyptic number.

664662551 is a deficient number, since it is larger than the sum of its proper divisors (94951801).

664662551 is an equidigital number, since it uses as much as digits as its factorization.

664662551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94951800.

The product of its digits is 259200, while the sum is 41.

The square root of 664662551 is about 25781.0502307412. The cubic root of 664662551 is about 872.7042079411.

The spelling of 664662551 in words is "six hundred sixty-four million, six hundred sixty-two thousand, five hundred fifty-one".