8188721461 has 8 divisors (see below), whose sum is σ = 8234832600. Its totient is φ = 8142700800.

The previous prime is 8188721371. The next prime is 8188721467. The reversal of 8188721461 is 1641278818.

It can be written as a sum of positive squares in 4 ways, for example, as 3259839025 + 4928882436 = 57095^2 + 70206^2 .

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 8188721461 - 2⁹ = 8188720949 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8188721467) 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, 163161 + ... + 207361.

It is an arithmetic number, because the mean of its divisors is an integer number (1029354075).

Almost surely, 2^8188721461 is an apocalyptic number.

It is an amenable number.

8188721461 is a deficient number, since it is larger than the sum of its proper divisors (46111139).

8188721461 is a wasteful number, since it uses less digits than its factorization.

8188721461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45239.

The product of its digits is 172032, while the sum is 46.

The square root of 8188721461 is about 90491.5546390933. The cubic root of 8188721461 is about 2015.6047181473.

The spelling of 8188721461 in words is "eight billion, one hundred eighty-eight million, seven hundred twenty-one thousand, four hundred sixty-one".