2158531601 has 8 divisors (see below), whose sum is σ = 2164058664. Its totient is φ = 2153013120.

The previous prime is 2158531547. The next prime is 2158531621. The reversal of 2158531601 is 1061358512.

It is a Cunningham number, because it is equal to 46460²+1.

It can be written as a sum of positive squares in 4 ways, for example, as 5664400 + 2152867201 = 2380^2 + 46399^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2158531601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2158531621) 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, 940211 + ... + 942503.

It is an arithmetic number, because the mean of its divisors is an integer number (270507333).

Almost surely, 2^2158531601 is an apocalyptic number.

It is an amenable number.

2158531601 is a deficient number, since it is larger than the sum of its proper divisors (5527063).

2158531601 is a wasteful number, since it uses less digits than its factorization.

2158531601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4291.

The product of its (nonzero) digits is 7200, while the sum is 32.

The square root of 2158531601 is about 46460.0000107619. Note that the first 4 decimals coincide. The cubic root of 2158531601 is about 1292.3678244918.

The spelling of 2158531601 in words is "two billion, one hundred fifty-eight million, five hundred thirty-one thousand, six hundred one".