1639972390 has 32 divisors (see below), whose sum is σ = 3403529280. Its totient is φ = 557297664.

The previous prime is 1639972379. The next prime is 1639972393. The reversal of 1639972390 is 932799361.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1639972393) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 95755 + ... + 111574.

It is an arithmetic number, because the mean of its divisors is an integer number (106360290).

Almost surely, 2^1639972390 is an apocalyptic number.

1639972390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1639972390 is an abundant number, since it is smaller than the sum of its proper divisors (1763556890).

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

1639972390 is a wasteful number, since it uses less digits than its factorization.

1639972390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207456.

The product of its (nonzero) digits is 551124, while the sum is 49.

The square root of 1639972390 is about 40496.5725710214. The cubic root of 1639972390 is about 1179.2670901222.

The spelling of 1639972390 in words is "one billion, six hundred thirty-nine million, nine hundred seventy-two thousand, three hundred ninety".