1640743507 has 4 divisors (see below), whose sum is σ = 1766954560. Its totient is φ = 1514532456.

The previous prime is 1640743487. The next prime is 1640743543. The reversal of 1640743507 is 7053470461.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1640743507 - 2¹⁵ = 1640710739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1640743007) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 63105507 + ... + 63105532.

It is an arithmetic number, because the mean of its divisors is an integer number (441738640).

Almost surely, 2^1640743507 is an apocalyptic number.

1640743507 is a deficient number, since it is larger than the sum of its proper divisors (126211053).

1640743507 is a wasteful number, since it uses less digits than its factorization.

1640743507 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126211052.

The product of its (nonzero) digits is 70560, while the sum is 37.

The square root of 1640743507 is about 40506.0922208006. The cubic root of 1640743507 is about 1179.4518920975.

The spelling of 1640743507 in words is "one billion, six hundred forty million, seven hundred forty-three thousand, five hundred seven".