1640240906 has 8 divisors (see below), whose sum is σ = 2567333664. Its totient is φ = 784463020.

The previous prime is 1640240879. The next prime is 1640240923. The reversal of 1640240906 is 6090420461.

It is a happy number.

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17828660 + ... + 17828751.

It is an arithmetic number, because the mean of its divisors is an integer number (320916708).

Almost surely, 2^1640240906 is an apocalyptic number.

1640240906 is a deficient number, since it is larger than the sum of its proper divisors (927092758).

1640240906 is a wasteful number, since it uses less digits than its factorization.

1640240906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35657436.

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 1640240906 is about 40499.8877282394. The cubic root of 1640240906 is about 1179.3314478726.

The spelling of 1640240906 in words is "one billion, six hundred forty million, two hundred forty thousand, nine hundred six".