401694981 has 4 divisors (see below), whose sum is σ = 535593312. Its totient is φ = 267796652.

The previous prime is 401694971. The next prime is 401694991. The reversal of 401694981 is 189496104.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (401694971) and next prime (401694991).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-401694981 is a prime.

It is a super-2 number, since 2×401694981² = 322717715521180722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (401694971) 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, 66949161 + ... + 66949166.

It is an arithmetic number, because the mean of its divisors is an integer number (133898328).

Almost surely, 2^401694981 is an apocalyptic number.

It is an amenable number.

401694981 is a deficient number, since it is larger than the sum of its proper divisors (133898331).

401694981 is a wasteful number, since it uses less digits than its factorization.

401694981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133898330.

The product of its (nonzero) digits is 62208, while the sum is 42.

The square root of 401694981 is about 20042.3297298493. The cubic root of 401694981 is about 737.8455604005.

It can be divided in two parts, 40169 and 4981, that added together give a triangular number (45150 = T₃₀₀).

The spelling of 401694981 in words is "four hundred one million, six hundred ninety-four thousand, nine hundred eighty-one".