245521690 has 8 divisors (see below), whose sum is σ = 441939060. Its totient is φ = 98208672.

The previous prime is 245521681. The next prime is 245521693. The reversal of 245521690 is 96125542.

It is a happy number.

245521690 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 221325129 + 24196561 = 14877^2 + 4919^2 .

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

It is a super-2 number, since 2×245521690² = 120561800520912200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (245521693) 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, 12276075 + ... + 12276094.

Almost surely, 2^245521690 is an apocalyptic number.

245521690 is a deficient number, since it is larger than the sum of its proper divisors (196417370).

245521690 is a wasteful number, since it uses less digits than its factorization.

245521690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24552176.

The product of its (nonzero) digits is 21600, while the sum is 34.

The square root of 245521690 is about 15669.1317564184. The cubic root of 245521690 is about 626.1762935447.

The spelling of 245521690 in words is "two hundred forty-five million, five hundred twenty-one thousand, six hundred ninety".