9975857781 has 8 divisors (see below), whose sum is σ = 13879454400. Its totient is φ = 6361416512.

The previous prime is 9975857777. The next prime is 9975857791. The reversal of 9975857781 is 1877585799.

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

It is a cyclic number.

It is not a de Polignac number, because 9975857781 - 2² = 9975857777 is a prime.

It is a super-2 number, since 2×9975857781² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9975857791) 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, 72288756 + ... + 72288893.

It is an arithmetic number, because the mean of its divisors is an integer number (1734931800).

Almost surely, 2^9975857781 is an apocalyptic number.

It is an amenable number.

9975857781 is a deficient number, since it is larger than the sum of its proper divisors (3903596619).

9975857781 is a wasteful number, since it uses less digits than its factorization.

9975857781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144577675.

The product of its digits is 44452800, while the sum is 66.

The square root of 9975857781 is about 99879.2159610797. The cubic root of 9975857781 is about 2152.6995317926.

The spelling of 9975857781 in words is "nine billion, nine hundred seventy-five million, eight hundred fifty-seven thousand, seven hundred eighty-one".