645267633 has 16 divisors (see below), whose sum is σ = 880056576. Its totient is φ = 420392960.

The previous prime is 645267583. The next prime is 645267641. The reversal of 645267633 is 336762546.

It is a cyclic number.

It is not a de Polignac number, because 645267633 - 2¹⁷ = 645136561 is a prime.

It is not an unprimeable number, because it can be changed into a prime (645217633) 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, 32968 + ... + 48758.

It is an arithmetic number, because the mean of its divisors is an integer number (55003536).

Almost surely, 2^645267633 is an apocalyptic number.

It is an amenable number.

645267633 is a deficient number, since it is larger than the sum of its proper divisors (234788943).

645267633 is a wasteful number, since it uses less digits than its factorization.

645267633 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16104.

The product of its digits is 544320, while the sum is 42.

The square root of 645267633 is about 25402.1186714809. The cubic root of 645267633 is about 864.1317461885.

It can be divided in two parts, 645 and 267633, that added together give a triangular number (268278 = T₇₃₂).

The spelling of 645267633 in words is "six hundred forty-five million, two hundred sixty-seven thousand, six hundred thirty-three".