20351641 has 4 divisors (see below), whose sum is σ = 21422800. Its totient is φ = 19280484.

The previous prime is 20351633. The next prime is 20351647. The reversal of 20351641 is 14615302.

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 a cyclic number.

It is not a de Polignac number, because 20351641 - 2³ = 20351633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20351647) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 535551 + ... + 535588.

It is an arithmetic number, because the mean of its divisors is an integer number (5355700).

Almost surely, 2^20351641 is an apocalyptic number.

It is an amenable number.

20351641 is a deficient number, since it is larger than the sum of its proper divisors (1071159).

20351641 is a wasteful number, since it uses less digits than its factorization.

20351641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1071158.

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 20351641 is about 4511.2793085776. The cubic root of 20351641 is about 273.0233625075.

Adding to 20351641 its reverse (14615302), we get a palindrome (34966943).

The spelling of 20351641 in words is "twenty million, three hundred fifty-one thousand, six hundred forty-one".