1628558261 has 8 divisors (see below), whose sum is σ = 1782934848. Its totient is φ = 1475236000.

The previous prime is 1628558257. The next prime is 1628558273.

1628558261 is nontrivially palindromic in base 10.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1628558261 - 2² = 1628558257 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 (1628558251) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 260345 + ... + 266526.

It is an arithmetic number, because the mean of its divisors is an integer number (222866856).

Almost surely, 2^1628558261 is an apocalyptic number.

1628558261 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1628558261 is a deficient number, since it is larger than the sum of its proper divisors (154376587).

1628558261 is a wasteful number, since it uses less digits than its factorization.

1628558261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 527163.

The product of its digits is 230400, while the sum is 44.

The square root of 1628558261 is about 40355.3994033017. The cubic root of 1628558261 is about 1176.5248375128.

The spelling of 1628558261 in words is "one billion, six hundred twenty-eight million, five hundred fifty-eight thousand, two hundred sixty-one".