25721901 has 16 divisors (see below), whose sum is σ = 40348800. Its totient is φ = 16138944.

The previous prime is 25721849. The next prime is 25721923. The reversal of 25721901 is 10912752.

25721901 is a `hidden beast` number, since 2 + 572 + 1 + 90 + 1 = 666.

It is not a de Polignac number, because 25721901 - 2¹¹ = 25719853 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25721701) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27561 + ... + 28478.

It is an arithmetic number, because the mean of its divisors is an integer number (2521800).

Almost surely, 2^25721901 is an apocalyptic number.

It is an amenable number.

25721901 is a deficient number, since it is larger than the sum of its proper divisors (14626899).

25721901 is a wasteful number, since it uses less digits than its factorization.

25721901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56065 (or 56059 counting only the distinct ones).

The product of its (nonzero) digits is 1260, while the sum is 27.

The square root of 25721901 is about 5071.6763500839. The cubic root of 25721901 is about 295.1895784212.

The spelling of 25721901 in words is "twenty-five million, seven hundred twenty-one thousand, nine hundred one".