645015431 has 2 divisors, whose sum is σ = 645015432. Its totient is φ = 645015430.

The previous prime is 645015383. The next prime is 645015467. The reversal of 645015431 is 134510546.

It is a happy number.

645015431 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 645015431 - 2¹⁰ = 645014407 is a prime.

It is a super-2 number, since 2×645015431² = 832089812456231522, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 645015394 and 645015403.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645015491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322507715 + 322507716.

It is an arithmetic number, because the mean of its divisors is an integer number (322507716).

Almost surely, 2^645015431 is an apocalyptic number.

645015431 is a deficient number, since it is larger than the sum of its proper divisors (1).

645015431 is an equidigital number, since it uses as much as digits as its factorization.

645015431 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7200, while the sum is 29.

The square root of 645015431 is about 25397.1539940994. The cubic root of 645015431 is about 864.0191499349.

Adding to 645015431 its reverse (134510546), we get a palindrome (779525977).

The spelling of 645015431 in words is "six hundred forty-five million, fifteen thousand, four hundred thirty-one".