8972818561 has 4 divisors (see below), whose sum is σ = 10254649792. Its totient is φ = 7690987332.

The previous prime is 8972818541. The next prime is 8972818567. The reversal of 8972818561 is 1658182798.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 8972818561 - 2¹³ = 8972810369 is a prime.

It is a super-2 number, since 2×8972818561² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8972818567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 640915605 + ... + 640915618.

It is an arithmetic number, because the mean of its divisors is an integer number (2563662448).

Almost surely, 2^8972818561 is an apocalyptic number.

It is an amenable number.

8972818561 is a deficient number, since it is larger than the sum of its proper divisors (1281831231).

8972818561 is a wasteful number, since it uses less digits than its factorization.

8972818561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1281831230.

The product of its digits is 1935360, while the sum is 55.

The square root of 8972818561 is about 94724.9627131096. The cubic root of 8972818561 is about 2077.9876494644.

The spelling of 8972818561 in words is "eight billion, nine hundred seventy-two million, eight hundred eighteen thousand, five hundred sixty-one".