1954561993 has 2 divisors, whose sum is σ = 1954561994. Its totient is φ = 1954561992.

The previous prime is 1954561967. The next prime is 1954562081. The reversal of 1954561993 is 3991654591.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1922208649 + 32353344 = 43843^2 + 5688^2 .

It is a cyclic number.

It is not a de Polignac number, because 1954561993 - 2¹⁷ = 1954430921 is a prime.

It is a super-3 number, since 3×1954561993³ (a number of 29 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1954561993.

It is not a weakly prime, because it can be changed into another prime (1954561913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 977280996 + 977280997.

It is an arithmetic number, because the mean of its divisors is an integer number (977280997).

Almost surely, 2^1954561993 is an apocalyptic number.

It is an amenable number.

1954561993 is a deficient number, since it is larger than the sum of its proper divisors (1).

1954561993 is an equidigital number, since it uses as much as digits as its factorization.

1954561993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1312200, while the sum is 52.

The square root of 1954561993 is about 44210.4285548105. The cubic root of 1954561993 is about 1250.3064833549.

The spelling of 1954561993 in words is "one billion, nine hundred fifty-four million, five hundred sixty-one thousand, nine hundred ninety-three".