1381381890 has 128 divisors (see below), whose sum is σ = 4002324480. Its totient is φ = 298080000.

The previous prime is 1381381889. The next prime is 1381381901. The reversal of 1381381890 is 981831831.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1839015 + ... + 1839765.

It is an arithmetic number, because the mean of its divisors is an integer number (31268160).

Almost surely, 2^1381381890 is an apocalyptic number.

1381381890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1381381890, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2001162240).

1381381890 is an abundant number, since it is smaller than the sum of its proper divisors (2620942590).

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

1381381890 is a wasteful number, since it uses less digits than its factorization.

1381381890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1248.

The product of its (nonzero) digits is 41472, while the sum is 42.

The square root of 1381381890 is about 37166.9462022373. The cubic root of 1381381890 is about 1113.7077779029.

It can be divided in two parts, 13813 and 81890, that added together give a triangular number (95703 = T₄₃₇).

The spelling of 1381381890 in words is "one billion, three hundred eighty-one million, three hundred eighty-one thousand, eight hundred ninety".