661470938651 has 8 divisors (see below), whose sum is σ = 696754739520. Its totient is φ = 626234091912.

The previous prime is 661470938641. The next prime is 661470938657. The reversal of 661470938651 is 156839074166.

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

It is not a de Polignac number, because 661470938651 - 2²⁶ = 661403829787 is a prime.

It is not an unprimeable number, because it can be changed into a prime (661470938657) 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, 11709605 + ... + 11765958.

It is an arithmetic number, because the mean of its divisors is an integer number (87094342440).

Almost surely, 2^661470938651 is an apocalyptic number.

661470938651 is a deficient number, since it is larger than the sum of its proper divisors (35283800869).

661470938651 is a wasteful number, since it uses less digits than its factorization.

661470938651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23477065.

The product of its (nonzero) digits is 6531840, while the sum is 56.

The spelling of 661470938651 in words is "six hundred sixty-one billion, four hundred seventy million, nine hundred thirty-eight thousand, six hundred fifty-one".