645379051 has 4 divisors (see below), whose sum is σ = 645508432. Its totient is φ = 645249672.

The previous prime is 645379019. The next prime is 645379093. The reversal of 645379051 is 150973546.

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 645379051 - 2⁵ = 645379019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 645378995 and 645379013.

It is not an unprimeable number, because it can be changed into a prime (645379751) 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, 56895 + ... + 67288.

It is an arithmetic number, because the mean of its divisors is an integer number (161377108).

Almost surely, 2^645379051 is an apocalyptic number.

645379051 is a deficient number, since it is larger than the sum of its proper divisors (129381).

645379051 is a wasteful number, since it uses less digits than its factorization.

645379051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129380.

The product of its (nonzero) digits is 113400, while the sum is 40.

The square root of 645379051 is about 25404.3116616058. The cubic root of 645379051 is about 864.1814797073.

The spelling of 645379051 in words is "six hundred forty-five million, three hundred seventy-nine thousand, fifty-one".