906551881 has 3 divisors (see below), whose sum is σ = 906581991. Its totient is φ = 906521772.

The previous prime is 906551873. The next prime is 906551951. The reversal of 906551881 is 188155609.

The square root of 906551881 is 30109.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 321879481 + 584672400 = 17941^2 + 24180^2 .

It is not a de Polignac number, because 906551881 - 2³ = 906551873 is a prime.

It is a super-2 number, since 2×906551881² = 1643672625889276322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (906551851) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 15055 + ... + 45163.

It is an arithmetic number, because the mean of its divisors is an integer number (302193997).

Almost surely, 2^906551881 is an apocalyptic number.

906551881 is the 30109-th square number.

906551881 is the 15055-th centered octagonal number.

It is an amenable number.

906551881 is a deficient number, since it is larger than the sum of its proper divisors (30110).

906551881 is an frugal number, since it uses more digits than its factorization.

906551881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60218 (or 30109 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 43.

The cubic root of 906551881 is about 967.8266005601.

The spelling of 906551881 in words is "nine hundred six million, five hundred fifty-one thousand, eight hundred eighty-one".