1913100121 has 9 divisors (see below), whose sum is σ = 1931603583. Its totient is φ = 1894773480.

The previous prime is 1913100109. The next prime is 1913100131. The reversal of 1913100121 is 1210013191.

The square root of 1913100121 is 43739.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 1781768521 + 131331600 = 42211^2 + 11460^2 .

It is not a de Polignac number, because 1913100121 - 2⁵ = 1913100089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1913100131) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 8354035 + ... + 8354263.

Almost surely, 2^1913100121 is an apocalyptic number.

1913100121 is the 43739-th square number.

1913100121 is the 21870-th centered octagonal number.

It is an amenable number.

1913100121 is a deficient number, since it is larger than the sum of its proper divisors (18503462).

1913100121 is an frugal number, since it uses more digits than its factorization.

1913100121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 840 (or 420 counting only the distinct ones).

The product of its (nonzero) digits is 54, while the sum is 19.

The cubic root of 1913100121 is about 1241.4023591849.

The spelling of 1913100121 in words is "one billion, nine hundred thirteen million, one hundred thousand, one hundred twenty-one".