20401025 has 24 divisors (see below), whose sum is σ = 26214840. Its totient is φ = 15741440.

The previous prime is 20401021. The next prime is 20401033. The reversal of 20401025 is 52010402.

It can be written as a sum of positive squares in 12 ways, for example, as 2347024 + 18054001 = 1532^2 + 4249^2 .

It is not a de Polignac number, because 20401025 - 2² = 20401021 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20401021) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 117839 + ... + 118011.

It is an arithmetic number, because the mean of its divisors is an integer number (1092285).

Almost surely, 2^20401025 is an apocalyptic number.

20401025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20401025 is a deficient number, since it is larger than the sum of its proper divisors (5813815).

20401025 is a wasteful number, since it uses less digits than its factorization.

20401025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 325 (or 320 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 14.

The square root of 20401025 is about 4516.7493842364. The cubic root of 20401025 is about 273.2440178470.

Adding to 20401025 its reverse (52010402), we get a palindrome (72411427).

The spelling of 20401025 in words is "twenty million, four hundred one thousand, twenty-five".