1890404069 has 4 divisors (see below), whose sum is σ = 1989899040. Its totient is φ = 1790909100.

The previous prime is 1890404057. The next prime is 1890404081. The reversal of 1890404069 is 9604040981.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (1890404057) and next prime (1890404081).

It is a cyclic number.

It is not a de Polignac number, because 1890404069 - 2⁸ = 1890403813 is a prime.

It is a super-2 number, since 2×1890404069² = 7147255088183513522, 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 (1890404969) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49747457 + ... + 49747494.

It is an arithmetic number, because the mean of its divisors is an integer number (497474760).

Almost surely, 2^1890404069 is an apocalyptic number.

1890404069 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

1890404069 is a deficient number, since it is larger than the sum of its proper divisors (99494971).

1890404069 is an equidigital number, since it uses as much as digits as its factorization.

1890404069 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99494970.

The product of its (nonzero) digits is 62208, while the sum is 41.

The square root of 1890404069 is about 43478.7772252164. Note that the first 3 decimals coincide. The cubic root of 1890404069 is about 1236.4736939092.

The spelling of 1890404069 in words is "one billion, eight hundred ninety million, four hundred four thousand, sixty-nine".