2355421665 has 16 divisors (see below), whose sum is σ = 3870531648. Its totient is φ = 1222272576.

The previous prime is 2355421661. The next prime is 2355421681. The reversal of 2355421665 is 5661245532.

It is not a de Polignac number, because 2355421665 - 2² = 2355421661 is a prime.

It is a super-2 number, since 2×2355421665² = 11096022439902744450, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2355421661) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2121447 + ... + 2122556.

It is an arithmetic number, because the mean of its divisors is an integer number (241908228).

Almost surely, 2^2355421665 is an apocalyptic number.

It is an amenable number.

2355421665 is a deficient number, since it is larger than the sum of its proper divisors (1515109983).

2355421665 is a wasteful number, since it uses less digits than its factorization.

2355421665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4244048.

The product of its digits is 216000, while the sum is 39.

The square root of 2355421665 is about 48532.6865627692. The cubic root of 2355421665 is about 1330.5245382339.

The spelling of 2355421665 in words is "two billion, three hundred fifty-five million, four hundred twenty-one thousand, six hundred sixty-five".