99945561501 has 24 divisors (see below), whose sum is σ = 154542146304. Its totient is φ = 64481002560.

The previous prime is 99945561497. The next prime is 99945561559. The reversal of 99945561501 is 10516554999.

99945561501 is a `hidden beast` number, since 9 + 99 + 45 + 5 + 6 + 1 + 501 = 666.

It is not a de Polignac number, because 99945561501 - 2² = 99945561497 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99945561581) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6626316 + ... + 6641381.

It is an arithmetic number, because the mean of its divisors is an integer number (6439256096).

Almost surely, 2^99945561501 is an apocalyptic number.

It is an amenable number.

99945561501 is a deficient number, since it is larger than the sum of its proper divisors (54596584803).

99945561501 is a wasteful number, since it uses less digits than its factorization.

99945561501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13267743 (or 13267731 counting only the distinct ones).

The product of its (nonzero) digits is 2187000, while the sum is 54.

It can be divided in two parts, 999 and 45561501, that added together give a square (45562500 = 6750²).

The spelling of 99945561501 in words is "ninety-nine billion, nine hundred forty-five million, five hundred sixty-one thousand, five hundred one".