906021561 has 8 divisors (see below), whose sum is σ = 1209489280. Its totient is φ = 603284112.

The previous prime is 906021559. The next prime is 906021601. The reversal of 906021561 is 165120609.

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

It is not a de Polignac number, because 906021561 - 2¹ = 906021559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (906021541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 179665 + ... + 184638.

It is an arithmetic number, because the mean of its divisors is an integer number (151186160).

Almost surely, 2^906021561 is an apocalyptic number.

It is an amenable number.

906021561 is a deficient number, since it is larger than the sum of its proper divisors (303467719).

906021561 is a wasteful number, since it uses less digits than its factorization.

906021561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 365135.

The product of its (nonzero) digits is 3240, while the sum is 30.

The square root of 906021561 is about 30100.1920425767. The cubic root of 906021561 is about 967.6378421342.

The spelling of 906021561 in words is "nine hundred six million, twenty-one thousand, five hundred sixty-one".