505551001 has 4 divisors (see below), whose sum is σ = 505597312. Its totient is φ = 505504692.

The previous prime is 505550987. The next prime is 505551023. The reversal of 505551001 is 100155505.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 100155505 = 5 ⋅20031101.

It is a cyclic number.

It is not a de Polignac number, because 505551001 - 2⁷ = 505550873 is a prime.

It is a super-2 number, since 2×505551001² = 511163629224204002, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (505551041) 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, 3280 + ... + 31966.

It is an arithmetic number, because the mean of its divisors is an integer number (126399328).

Almost surely, 2^505551001 is an apocalyptic number.

It is an amenable number.

505551001 is a deficient number, since it is larger than the sum of its proper divisors (46311).

505551001 is a wasteful number, since it uses less digits than its factorization.

505551001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46310.

The product of its (nonzero) digits is 625, while the sum is 22.

The square root of 505551001 is about 22484.4613233228. The cubic root of 505551001 is about 796.6269444626.

The spelling of 505551001 in words is "five hundred five million, five hundred fifty-one thousand, one".