1990226381 has 32 divisors (see below), whose sum is σ = 2444574720. Its totient is φ = 1595505600.

The previous prime is 1990226377. The next prime is 1990226393. The reversal of 1990226381 is 1836220991.

It is not a de Polignac number, because 1990226381 - 2² = 1990226377 is a prime.

It is a super-2 number, since 2×1990226381² = 7922002095256714322, 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 (1990226681) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 347366 + ... + 353048.

It is an arithmetic number, because the mean of its divisors is an integer number (76392960).

Almost surely, 2^1990226381 is an apocalyptic number.

1990226381 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1990226381 is a deficient number, since it is larger than the sum of its proper divisors (454348339).

1990226381 is a wasteful number, since it uses less digits than its factorization.

1990226381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5817.

The product of its (nonzero) digits is 46656, while the sum is 41.

The square root of 1990226381 is about 44611.9533421257. The cubic root of 1990226381 is about 1257.8653662862.

The spelling of 1990226381 in words is "one billion, nine hundred ninety million, two hundred twenty-six thousand, three hundred eighty-one".