64378016251 has 4 divisors (see below), whose sum is σ = 64512417600. Its totient is φ = 64243614904.

The previous prime is 64378016237. The next prime is 64378016281. The reversal of 64378016251 is 15261087346.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 64378016251 - 2¹³ = 64378008059 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 64378016198 and 64378016207.

It is not an unprimeable number, because it can be changed into a prime (64378016281) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 67199956 + ... + 67200913.

It is an arithmetic number, because the mean of its divisors is an integer number (16128104400).

Almost surely, 2^64378016251 is an apocalyptic number.

64378016251 is a deficient number, since it is larger than the sum of its proper divisors (134401349).

64378016251 is a wasteful number, since it uses less digits than its factorization.

64378016251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134401348.

The product of its (nonzero) digits is 241920, while the sum is 43.

The spelling of 64378016251 in words is "sixty-four billion, three hundred seventy-eight million, sixteen thousand, two hundred fifty-one".