20151649 has 8 divisors (see below), whose sum is σ = 23566400. Its totient is φ = 16870896.

The previous prime is 20151619. The next prime is 20151667. The reversal of 20151649 is 94615102.

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

It is not a de Polignac number, because 20151649 - 2⁵ = 20151617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20151619) 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, 33174 + ... + 33775.

It is an arithmetic number, because the mean of its divisors is an integer number (2945800).

Almost surely, 2^20151649 is an apocalyptic number.

It is an amenable number.

20151649 is a deficient number, since it is larger than the sum of its proper divisors (3414751).

20151649 is an equidigital number, since it uses as much as digits as its factorization.

20151649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66999.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 20151649 is about 4489.0588100403. The cubic root of 20151649 is about 272.1260994392.

The spelling of 20151649 in words is "twenty million, one hundred fifty-one thousand, six hundred forty-nine".