645261742 has 16 divisors (see below), whose sum is σ = 976483872. Its totient is φ = 319779360.

The previous prime is 645261739. The next prime is 645261767. The reversal of 645261742 is 247162546.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 111943 + ... + 117565.

It is an arithmetic number, because the mean of its divisors is an integer number (61030242).

Almost surely, 2^645261742 is an apocalyptic number.

645261742 is a deficient number, since it is larger than the sum of its proper divisors (331222130).

645261742 is a wasteful number, since it uses less digits than its factorization.

645261742 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6123.

The product of its digits is 80640, while the sum is 37.

The square root of 645261742 is about 25402.0027163214. The cubic root of 645261742 is about 864.1291164706.

The spelling of 645261742 in words is "six hundred forty-five million, two hundred sixty-one thousand, seven hundred forty-two".