42900051781 has 4 divisors (see below), whose sum is σ = 42900573100. Its totient is φ = 42899530464.

The previous prime is 42900051713. The next prime is 42900051823. The reversal of 42900051781 is 18715000924.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 36210284100 + 6689767681 = 190290^2 + 81791^2 .

It is a cyclic number.

It is not a de Polignac number, because 42900051781 - 2²¹ = 42897954629 is a prime.

It is a super-2 number, since 2×42900051781² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 42900051781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42900091781) 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, 107046 + ... + 311863.

It is an arithmetic number, because the mean of its divisors is an integer number (10725143275).

Almost surely, 2^42900051781 is an apocalyptic number.

It is an amenable number.

42900051781 is a deficient number, since it is larger than the sum of its proper divisors (521319).

42900051781 is a wasteful number, since it uses less digits than its factorization.

42900051781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 521318.

The product of its (nonzero) digits is 20160, while the sum is 37.

The spelling of 42900051781 in words is "forty-two billion, nine hundred million, fifty-one thousand, seven hundred eighty-one".