645023071 has 32 divisors (see below), whose sum is σ = 822804480. Its totient is φ = 491119200.

The previous prime is 645023069. The next prime is 645023081. The reversal of 645023071 is 170320546.

It is not a de Polignac number, because 645023071 - 2¹ = 645023069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645023021) 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, 650386 + ... + 651376.

It is an arithmetic number, because the mean of its divisors is an integer number (25712640).

Almost surely, 2^645023071 is an apocalyptic number.

645023071 is a deficient number, since it is larger than the sum of its proper divisors (177781409).

645023071 is a wasteful number, since it uses less digits than its factorization.

645023071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1195.

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 645023071 is about 25397.3044042079. The cubic root of 645023071 is about 864.0225612643.

The spelling of 645023071 in words is "six hundred forty-five million, twenty-three thousand, seventy-one".