401781439 has 4 divisors (see below), whose sum is σ = 406867360. Its totient is φ = 396695520.

The previous prime is 401781397. The next prime is 401781449. The reversal of 401781439 is 934187104.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 401781439 - 2¹³ = 401773247 is a prime.

It is a super-2 number, since 2×401781439² = 322856649449821442, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 401781398 and 401781407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (401781449) 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, 2542842 + ... + 2542999.

It is an arithmetic number, because the mean of its divisors is an integer number (101716840).

Almost surely, 2^401781439 is an apocalyptic number.

401781439 is a deficient number, since it is larger than the sum of its proper divisors (5085921).

401781439 is an equidigital number, since it uses as much as digits as its factorization.

401781439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5085920.

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 401781439 is about 20044.4864987856. The cubic root of 401781439 is about 737.8984928312.

The spelling of 401781439 in words is "four hundred one million, seven hundred eighty-one thousand, four hundred thirty-nine".