2151521165 has 32 divisors (see below), whose sum is σ = 2736115200. Its totient is φ = 1621751040.

The previous prime is 2151521159. The next prime is 2151521191. The reversal of 2151521165 is 5611251512.

It is not a de Polignac number, because 2151521165 - 2⁴ = 2151521149 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1059371 + ... + 1061399.

It is an arithmetic number, because the mean of its divisors is an integer number (85503600).

Almost surely, 2^2151521165 is an apocalyptic number.

It is an amenable number.

2151521165 is a deficient number, since it is larger than the sum of its proper divisors (584594035).

2151521165 is a wasteful number, since it uses less digits than its factorization.

2151521165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2237.

The product of its digits is 3000, while the sum is 29.

The square root of 2151521165 is about 46384.4927211671. The cubic root of 2151521165 is about 1290.9671982487.

Adding to 2151521165 its reverse (5611251512), we get a palindrome (7762772677).

The spelling of 2151521165 in words is "two billion, one hundred fifty-one million, five hundred twenty-one thousand, one hundred sixty-five".