405661025 has 48 divisors (see below), whose sum is σ = 629959680. Its totient is φ = 251745600.

The previous prime is 405661013. The next prime is 405661027. The reversal of 405661025 is 520166504.

It is a de Polignac number, because none of the positive numbers 2^k-405661025 is a prime.

It is not an unprimeable number, because it can be changed into a prime (405661027) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 690782 + ... + 691368.

It is an arithmetic number, because the mean of its divisors is an integer number (13124160).

Almost surely, 2^405661025 is an apocalyptic number.

It is an amenable number.

405661025 is a deficient number, since it is larger than the sum of its proper divisors (224298655).

405661025 is a wasteful number, since it uses less digits than its factorization.

405661025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 974 (or 969 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 29.

The square root of 405661025 is about 20141.0283997615. The cubic root of 405661025 is about 740.2659288939.

The spelling of 405661025 in words is "four hundred five million, six hundred sixty-one thousand, twenty-five".