225661213157 has 4 divisors (see below), whose sum is σ = 225665652576. Its totient is φ = 225656773740.

The previous prime is 225661213121. The next prime is 225661213181. The reversal of 225661213157 is 751312166522.

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 225661213157 - 2³⁰ = 224587471333 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (225661213117) 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, 2142569 + ... + 2245422.

It is an arithmetic number, because the mean of its divisors is an integer number (56416413144).

Almost surely, 2^225661213157 is an apocalyptic number.

It is an amenable number.

225661213157 is a deficient number, since it is larger than the sum of its proper divisors (4439419).

225661213157 is an equidigital number, since it uses as much as digits as its factorization.

225661213157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4439418.

The product of its digits is 151200, while the sum is 41.

Adding to 225661213157 its reverse (751312166522), we get a palindrome (976973379679).

The spelling of 225661213157 in words is "two hundred twenty-five billion, six hundred sixty-one million, two hundred thirteen thousand, one hundred fifty-seven".