51640025 has 12 divisors (see below), whose sum is σ = 64755900. Its totient is φ = 40846080.

The previous prime is 51640007. The next prime is 51640031. The reversal of 51640025 is 52004615.

It can be written as a sum of positive squares in 6 ways, for example, as 1669264 + 49970761 = 1292^2 + 7069^2 .

It is not a de Polignac number, because 51640025 - 2⁶ = 51639961 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9380 + ... + 13829.

It is an arithmetic number, because the mean of its divisors is an integer number (5396325).

Almost surely, 2^51640025 is an apocalyptic number.

It is an amenable number.

51640025 is a deficient number, since it is larger than the sum of its proper divisors (13115875).

51640025 is a wasteful number, since it uses less digits than its factorization.

51640025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23308 (or 23303 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 51640025 is about 7186.0994287583. The cubic root of 51640025 is about 372.3878316384.

The spelling of 51640025 in words is "fifty-one million, six hundred forty thousand, twenty-five".