1640656550 has 24 divisors (see below), whose sum is σ = 3286362576. Its totient is φ = 605780640.

The previous prime is 1640656543. The next prime is 1640656561. The reversal of 1640656550 is 556560461.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1261394 + ... + 1262693.

It is an arithmetic number, because the mean of its divisors is an integer number (136931774).

Almost surely, 2^1640656550 is an apocalyptic number.

1640656550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1640656550 is an abundant number, since it is smaller than the sum of its proper divisors (1645706026).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1640656550 is a wasteful number, since it uses less digits than its factorization.

1640656550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2524112 (or 2524107 counting only the distinct ones).

The product of its (nonzero) digits is 108000, while the sum is 38.

The square root of 1640656550 is about 40505.0188248321. The cubic root of 1640656550 is about 1179.4310553225.

The spelling of 1640656550 in words is "one billion, six hundred forty million, six hundred fifty-six thousand, five hundred fifty".