398878155493 has 4 divisors (see below), whose sum is σ = 409658646220. Its totient is φ = 388097664768.

The previous prime is 398878155469. The next prime is 398878155517. The reversal of 398878155493 is 394551878893.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 394551878893 = 149551 ⋅2638243.

It is an interprime number because it is at equal distance from previous prime (398878155469) and next prime (398878155517).

It can be written as a sum of positive squares in 2 ways, for example, as 215516920644 + 183361234849 = 464238^2 + 428207^2 .

It is a cyclic number.

It is not a de Polignac number, because 398878155493 - 2¹⁷ = 398878024421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (398878150493) 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, 5390245308 + ... + 5390245381.

It is an arithmetic number, because the mean of its divisors is an integer number (102414661555).

Almost surely, 2^398878155493 is an apocalyptic number.

It is an amenable number.

398878155493 is a deficient number, since it is larger than the sum of its proper divisors (10780490727).

398878155493 is a wasteful number, since it uses less digits than its factorization.

398878155493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10780490726.

The product of its digits is 261273600, while the sum is 70.

The spelling of 398878155493 in words is "three hundred ninety-eight billion, eight hundred seventy-eight million, one hundred fifty-five thousand, four hundred ninety-three".