661562001 has 12 divisors (see below), whose sum is σ = 956835828. Its totient is φ = 440466144.

The previous prime is 661561997. The next prime is 661562017. The reversal of 661562001 is 100265166.

It is a happy number.

661562001 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 25765776 + 635796225 = 5076^2 + 25215^2 .

It is not a de Polignac number, because 661562001 - 2² = 661561997 is a prime.

It is not an unprimeable number, because it can be changed into a prime (661562071) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 40590 + ... + 54503.

It is an arithmetic number, because the mean of its divisors is an integer number (79736319).

Almost surely, 2^661562001 is an apocalyptic number.

It is an amenable number.

661562001 is a deficient number, since it is larger than the sum of its proper divisors (295273827).

661562001 is a wasteful number, since it uses less digits than its factorization.

661562001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95872 (or 95869 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 661562001 is about 25720.8475948986. The cubic root of 661562001 is about 871.3450814460.

The spelling of 661562001 in words is "six hundred sixty-one million, five hundred sixty-two thousand, one".