645147420 has 48 divisors (see below), whose sum is σ = 1815615648. Its totient is φ = 171162880.

The previous prime is 645147403. The next prime is 645147421. The reversal of 645147420 is 24741546.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645147421) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15471 + ... + 39110.

It is an arithmetic number, because the mean of its divisors is an integer number (37825326).

Almost surely, 2^645147420 is an apocalyptic number.

645147420 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

645147420 is an abundant number, since it is smaller than the sum of its proper divisors (1170468228).

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

645147420 is a wasteful number, since it uses less digits than its factorization.

645147420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54790 (or 54788 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 33.

The square root of 645147420 is about 25399.7523609975. The cubic root of 645147420 is about 864.0780804350.

Adding to 645147420 its reverse (24741546), we get a palindrome (669888966).

The spelling of 645147420 in words is "six hundred forty-five million, one hundred forty-seven thousand, four hundred twenty".