1690945920 has 384 divisors, whose sum is σ = 6186585600. Its totient is φ = 424919040.

The previous prime is 1690945897. The next prime is 1690945937. The reversal of 1690945920 is 295490961.

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 8853025 + ... + 8853215.

It is an arithmetic number, because the mean of its divisors is an integer number (16110900).

Almost surely, 2^1690945920 is an apocalyptic number.

1690945920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1690945920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3093292800).

1690945920 is an abundant number, since it is smaller than the sum of its proper divisors (4495639680).

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

1690945920 is a wasteful number, since it uses less digits than its factorization.

1690945920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298 (or 283 counting only the distinct ones).

The product of its (nonzero) digits is 174960, while the sum is 45.

The square root of 1690945920 is about 41121.1128254088. The cubic root of 1690945920 is about 1191.3606168157.

The spelling of 1690945920 in words is "one billion, six hundred ninety million, nine hundred forty-five thousand, nine hundred twenty".