645013651 has 8 divisors (see below), whose sum is σ = 647342640. Its totient is φ = 642690048.

The previous prime is 645013627. The next prime is 645013661. The reversal of 645013651 is 156310546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 645013651 - 2¹⁵ = 644980883 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645013661) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 529395 + ... + 530611.

It is an arithmetic number, because the mean of its divisors is an integer number (80917830).

Almost surely, 2^645013651 is an apocalyptic number.

645013651 is a deficient number, since it is larger than the sum of its proper divisors (2328989).

645013651 is a wasteful number, since it uses less digits than its factorization.

645013651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2693.

The product of its (nonzero) digits is 10800, while the sum is 31.

The square root of 645013651 is about 25397.1189507786. The cubic root of 645013651 is about 864.0183551449.

The spelling of 645013651 in words is "six hundred forty-five million, thirteen thousand, six hundred fifty-one".