400442168025 has 27 divisors (see below), whose sum is σ = 717253418271. Its totient is φ = 213564093840.

The previous prime is 400442167933. The next prime is 400442168047. The reversal of 400442168025 is 520861244004.

The square root of 400442168025 is 632805.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 144159180489 + 256282987536 = 379683^2 + 506244^2 .

It is not a de Polignac number, because 400442168025 - 2²⁵ = 400408613593 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 9470982 + ... + 9513168.

Almost surely, 2^400442168025 is an apocalyptic number.

400442168025 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

400442168025 is the 632805-th square number.

400442168025 is the 316403-rd centered octagonal number.

It is an amenable number.

400442168025 is a deficient number, since it is larger than the sum of its proper divisors (316811250246).

400442168025 is an frugal number, since it uses more digits than its factorization.

400442168025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84390 (or 42195 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 36.

Multiplying 400442168025 by its sum of digits (36), we get a square (14415918048900 = 3796830²).

The spelling of 400442168025 in words is "four hundred billion, four hundred forty-two million, one hundred sixty-eight thousand, twenty-five".