661617274634 has 16 divisors (see below), whose sum is σ = 997502155776. Its totient is φ = 329117728800.

The previous prime is 661617274607. The next prime is 661617274639. The reversal of 661617274634 is 436472716166.

661617274634 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (661617274639) 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, 842174 + ... + 1425654.

It is an arithmetic number, because the mean of its divisors is an integer number (62343884736).

Almost surely, 2^661617274634 is an apocalyptic number.

661617274634 is a deficient number, since it is larger than the sum of its proper divisors (335884881142).

661617274634 is a wasteful number, since it uses less digits than its factorization.

661617274634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 586381.

The product of its digits is 6096384, while the sum is 53.

The spelling of 661617274634 in words is "six hundred sixty-one billion, six hundred seventeen million, two hundred seventy-four thousand, six hundred thirty-four".