645700498 has 4 divisors (see below), whose sum is σ = 968550750. Its totient is φ = 322850248.

The previous prime is 645700481. The next prime is 645700571. The reversal of 645700498 is 894007546.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 894007546 = 2 ⋅447003773.

It can be written as a sum of positive squares in only one way, i.e., 324108009 + 321592489 = 18003^2 + 17933^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 161425123 + ... + 161425126.

Almost surely, 2^645700498 is an apocalyptic number.

645700498 is a deficient number, since it is larger than the sum of its proper divisors (322850252).

645700498 is a wasteful number, since it uses less digits than its factorization.

645700498 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322850251.

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

The square root of 645700498 is about 25410.6374969224. The cubic root of 645700498 is about 864.3249315473.

The spelling of 645700498 in words is "six hundred forty-five million, seven hundred thousand, four hundred ninety-eight".