401357781 has 16 divisors (see below), whose sum is σ = 648659520. Its totient is φ = 243246960.

The previous prime is 401357771. The next prime is 401357791. The reversal of 401357781 is 187753104.

401357781 is a `hidden beast` number, since 4 + 0 + 1 + 3 + 577 + 81 = 666.

It is an interprime number because it is at equal distance from previous prime (401357771) and next prime (401357791).

It is not a de Polignac number, because 401357781 - 2⁶ = 401357717 is a prime.

It is a super-2 number, since 2×401357781² = 322176136738487922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (401357701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 675390 + ... + 675983.

It is an arithmetic number, because the mean of its divisors is an integer number (40541220).

Almost surely, 2^401357781 is an apocalyptic number.

It is an amenable number.

401357781 is a deficient number, since it is larger than the sum of its proper divisors (247301739).

401357781 is a wasteful number, since it uses less digits than its factorization.

401357781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1351393 (or 1351387 counting only the distinct ones).

The product of its (nonzero) digits is 23520, while the sum is 36.

The square root of 401357781 is about 20033.9157680170. The cubic root of 401357781 is about 737.6390428640.

The spelling of 401357781 in words is "four hundred one million, three hundred fifty-seven thousand, seven hundred eighty-one".