664647742 has 16 divisors (see below), whose sum is σ = 1151582832. Its totient is φ = 284341120.

The previous prime is 664647733. The next prime is 664647743. The reversal of 664647742 is 247746466.

It is a junction number, because it is equal to n+sod(n) for n = 664647692 and 664647701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664647743) 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, 888193 + ... + 888940.

It is an arithmetic number, because the mean of its divisors is an integer number (71973927).

Almost surely, 2^664647742 is an apocalyptic number.

664647742 is a deficient number, since it is larger than the sum of its proper divisors (486935090).

664647742 is a wasteful number, since it uses less digits than its factorization.

664647742 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1777163.

The product of its digits is 1354752, while the sum is 46.

The square root of 664647742 is about 25780.7630220674. The cubic root of 664647742 is about 872.6977264704.

The spelling of 664647742 in words is "six hundred sixty-four million, six hundred forty-seven thousand, seven hundred forty-two".