645125001531 has 16 divisors (see below), whose sum is σ = 908779722240. Its totient is φ = 405943863840.

The previous prime is 645125001527. The next prime is 645125001533. The reversal of 645125001531 is 135100521546.

It is not a de Polignac number, because 645125001531 - 2² = 645125001527 is a prime.

It is a super-2 number, since 2×645125001531² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 645125001492 and 645125001501.

It is not an unprimeable number, because it can be changed into a prime (645125001533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20866440 + ... + 20897333.

It is an arithmetic number, because the mean of its divisors is an integer number (56798732640).

Almost surely, 2^645125001531 is an apocalyptic number.

645125001531 is a deficient number, since it is larger than the sum of its proper divisors (263654720709).

645125001531 is a wasteful number, since it uses less digits than its factorization.

645125001531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41764066.

The product of its (nonzero) digits is 18000, while the sum is 33.

The spelling of 645125001531 in words is "six hundred forty-five billion, one hundred twenty-five million, one thousand, five hundred thirty-one".