7901378646 has 64 divisors (see below), whose sum is σ = 19837440000. Its totient is φ = 2045726496.

The previous prime is 7901378621. The next prime is 7901378647. The reversal of 7901378646 is 6468731097.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7901378647) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 196896 + ... + 233603.

It is an arithmetic number, because the mean of its divisors is an integer number (309960000).

Almost surely, 2^7901378646 is an apocalyptic number.

7901378646 is an abundant number, since it is smaller than the sum of its proper divisors (11936061354).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7901378646 is a wasteful number, since it uses less digits than its factorization.

7901378646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 430553.

The product of its (nonzero) digits is 1524096, while the sum is 51.

The square root of 7901378646 is about 88889.6993244999. The cubic root of 7901378646 is about 1991.7475491959.

The spelling of 7901378646 in words is "seven billion, nine hundred one million, three hundred seventy-eight thousand, six hundred forty-six".