402018806461 has 4 divisors (see below), whose sum is σ = 402041108124. Its totient is φ = 401996504800.

The previous prime is 402018806437. The next prime is 402018806471. The reversal of 402018806461 is 164608810204.

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

It can be written as a sum of positive squares in 2 ways, for example, as 182427223225 + 219591583236 = 427115^2 + 468606^2 .

It is a cyclic number.

It is not a de Polignac number, because 402018806461 - 2⁷ = 402018806333 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402018806471) 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, 11123770 + ... + 11159851.

It is an arithmetic number, because the mean of its divisors is an integer number (100510277031).

Almost surely, 2^402018806461 is an apocalyptic number.

It is an amenable number.

402018806461 is a deficient number, since it is larger than the sum of its proper divisors (22301663).

402018806461 is a wasteful number, since it uses less digits than its factorization.

402018806461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22301662.

The product of its (nonzero) digits is 73728, while the sum is 40.

The spelling of 402018806461 in words is "four hundred two billion, eighteen million, eight hundred six thousand, four hundred sixty-one".