1361971890 has 48 divisors (see below), whose sum is σ = 3545889048. Its totient is φ = 362704128.

The previous prime is 1361971883. The next prime is 1361971943. The reversal of 1361971890 is 981791631.

1361971890 is a `hidden beast` number, since 13 + 619 + 7 + 18 + 9 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1103501961 + 258469929 = 33219^2 + 16077^2 .

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

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 23 ways as a sum of consecutive naturals, for example, 59782 + ... + 79358.

Almost surely, 2^1361971890 is an apocalyptic number.

1361971890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1361971890 is an abundant number, since it is smaller than the sum of its proper divisors (2183917158).

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

1361971890 is a wasteful number, since it uses less digits than its factorization.

1361971890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20363 (or 20360 counting only the distinct ones).

The product of its (nonzero) digits is 81648, while the sum is 45.

The square root of 1361971890 is about 36904.9033327551. The cubic root of 1361971890 is about 1108.4668631903.

The spelling of 1361971890 in words is "one billion, three hundred sixty-one million, nine hundred seventy-one thousand, eight hundred ninety".