245481981 has 4 divisors (see below), whose sum is σ = 327309312. Its totient is φ = 163654652.

The previous prime is 245481979. The next prime is 245482009. The reversal of 245481981 is 189184542.

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 245481981 - 2¹ = 245481979 is a prime.

It is a super-2 number, since 2×245481981² = 120522805991368722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (245481961) 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, 40913661 + ... + 40913666.

It is an arithmetic number, because the mean of its divisors is an integer number (81827328).

Almost surely, 2^245481981 is an apocalyptic number.

It is an amenable number.

245481981 is a deficient number, since it is larger than the sum of its proper divisors (81827331).

245481981 is an equidigital number, since it uses as much as digits as its factorization.

245481981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81827330.

The product of its digits is 92160, while the sum is 42.

The square root of 245481981 is about 15667.8645960450. The cubic root of 245481981 is about 626.1425339000.

The spelling of 245481981 in words is "two hundred forty-five million, four hundred eighty-one thousand, nine hundred eighty-one".