1780990381 has 8 divisors (see below), whose sum is σ = 1786500000. Its totient is φ = 1775489520.

The previous prime is 1780990373. The next prime is 1780990399. The reversal of 1780990381 is 1830990871.

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

It is a cyclic number.

It is not a de Polignac number, because 1780990381 - 2³ = 1780990373 is a prime.

It is a super-2 number, since 2×1780990381² = 6343853474429050322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1780990361) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 746811 + ... + 749191.

It is an arithmetic number, because the mean of its divisors is an integer number (223312500).

Almost surely, 2^1780990381 is an apocalyptic number.

It is an amenable number.

1780990381 is a deficient number, since it is larger than the sum of its proper divisors (5509619).

1780990381 is a wasteful number, since it uses less digits than its factorization.

1780990381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4379.

The product of its (nonzero) digits is 108864, while the sum is 46.

The square root of 1780990381 is about 42201.7817277896. The cubic root of 1780990381 is about 1212.1430003785.

The spelling of 1780990381 in words is "one billion, seven hundred eighty million, nine hundred ninety thousand, three hundred eighty-one".