645253626352546 has 4 divisors (see below), whose sum is σ = 967880439528822. Its totient is φ = 322626813176272.

The previous prime is 645253626352541. The next prime is 645253626352579.

645253626352546 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 622600357745521 + 22653268607025 = 24951961^2 + 4759545^2 .

It is a super-2 number, since 2×645253626352546² (a number of 30 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (645253626352541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 161313406588135 + ... + 161313406588138.

Almost surely, 2^{645253626352546} is an apocalyptic number.

645253626352546 is a deficient number, since it is larger than the sum of its proper divisors (322626813176276).

645253626352546 is a wasteful number, since it uses less digits than its factorization.

645253626352546 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322626813176275.

The product of its digits is 933120000, while the sum is 64.

The spelling of 645253626352546 in words is "six hundred forty-five trillion, two hundred fifty-three billion, six hundred twenty-six million, three hundred fifty-two thousand, five hundred forty-six".