401660778 has 32 divisors (see below), whose sum is σ = 824069376. Its totient is φ = 130454528.

The previous prime is 401660767. The next prime is 401660813. The reversal of 401660778 is 877066104.

It is a super-2 number, since 2×401660778² = 322662761167130568, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 62650 + ... + 68762.

It is an arithmetic number, because the mean of its divisors is an integer number (25752168).

Almost surely, 2^401660778 is an apocalyptic number.

401660778 is an abundant number, since it is smaller than the sum of its proper divisors (422408598).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

401660778 is a wasteful number, since it uses less digits than its factorization.

401660778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6398.

The product of its (nonzero) digits is 56448, while the sum is 39.

The square root of 401660778 is about 20041.4764426177. The cubic root of 401660778 is about 737.8246181025.

The spelling of 401660778 in words is "four hundred one million, six hundred sixty thousand, seven hundred seventy-eight".