19965615646956 has 48 divisors (see below), whose sum is σ = 53303335593984. Its totient is φ = 5697851556096.

The previous prime is 19965615646811. The next prime is 19965615646957. The reversal of 19965615646956 is 65964651656991.

It is not an unprimeable number, because it can be changed into a prime (19965615646957) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 137636605 + ... + 137781588.

It is an arithmetic number, because the mean of its divisors is an integer number (1110486158208).

Almost surely, 2^{19965615646956} is an apocalyptic number.

It is an amenable number.

19965615646956 is an abundant number, since it is smaller than the sum of its proper divisors (33337719947028).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19965615646956 is a wasteful number, since it uses less digits than its factorization.

19965615646956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 275419070 (or 275419068 counting only the distinct ones).

The product of its digits is 2834352000, while the sum is 78.

The spelling of 19965615646956 in words is "nineteen trillion, nine hundred sixty-five billion, six hundred fifteen million, six hundred forty-six thousand, nine hundred fifty-six".