401561647 has 4 divisors (see below), whose sum is σ = 403664256. Its totient is φ = 399459040.

The previous prime is 401561627. The next prime is 401561653. The reversal of 401561647 is 746165104.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 401561647 - 2⁷ = 401561519 is a prime.

It is a super-3 number, since 3×401561647³ (a number of 27 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (401561617) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1051018 + ... + 1051399.

It is an arithmetic number, because the mean of its divisors is an integer number (100916064).

Almost surely, 2^401561647 is an apocalyptic number.

401561647 is a deficient number, since it is larger than the sum of its proper divisors (2102609).

401561647 is a wasteful number, since it uses less digits than its factorization.

401561647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2102608.

The product of its (nonzero) digits is 20160, while the sum is 34.

The square root of 401561647 is about 20039.0031438692. The cubic root of 401561647 is about 737.7639140505.

The spelling of 401561647 in words is "four hundred one million, five hundred sixty-one thousand, six hundred forty-seven".