1551085205 has 4 divisors (see below), whose sum is σ = 1861302252. Its totient is φ = 1240868160.

The previous prime is 1551085199. The next prime is 1551085229. The reversal of 1551085205 is 5025801551.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5025801551 = 197 ⋅25511683.

It can be written as a sum of positive squares in 2 ways, for example, as 568011889 + 983073316 = 23833^2 + 31354^2 .

It is not a de Polignac number, because 1551085205 - 2¹² = 1551081109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 155108516 + ... + 155108525.

It is an arithmetic number, because the mean of its divisors is an integer number (465325563).

Almost surely, 2^1551085205 is an apocalyptic number.

It is an amenable number.

1551085205 is a deficient number, since it is larger than the sum of its proper divisors (310217047).

1551085205 is an equidigital number, since it uses as much as digits as its factorization.

1551085205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 310217046.

The product of its (nonzero) digits is 10000, while the sum is 32.

The square root of 1551085205 is about 39383.8190758591. The cubic root of 1551085205 is about 1157.5645506656.

Adding to 1551085205 its reverse (5025801551), we get a palindrome (6576886756).

The spelling of 1551085205 in words is "one billion, five hundred fifty-one million, eighty-five thousand, two hundred five".