1690780090 has 12 divisors (see below), whose sum is σ = 3043638234. Its totient is φ = 676260024.

The previous prime is 1690780087. The next prime is 1690780093. The reversal of 1690780090 is 900870961.

It is an interprime number because it is at equal distance from previous prime (1690780087) and next prime (1690780093).

It can be written as a sum of positive squares in only one way, i.e., 1521702081 + 169078009 = 39009^2 + 13003^2 .

It is not an unprimeable number, because it can be changed into a prime (1690780093) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 123529 + ... + 136531.

Almost surely, 2^1690780090 is an apocalyptic number.

1690780090 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1690780090 is a deficient number, since it is larger than the sum of its proper divisors (1352858144).

1690780090 is an frugal number, since it uses more digits than its factorization.

1690780090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26013 (or 13010 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 40.

The square root of 1690780090 is about 41119.0964151694. The cubic root of 1690780090 is about 1191.3216702144.

Multiplying 1690780090 by its sum of digits (40), we get a square (67631203600 = 260060²).

The spelling of 1690780090 in words is "one billion, six hundred ninety million, seven hundred eighty thousand, ninety".