1201778623 has 4 divisors (see below), whose sum is σ = 1201860688. Its totient is φ = 1201696560.

The previous prime is 1201778597. The next prime is 1201778653. The reversal of 1201778623 is 3268771021.

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 is a cyclic number.

It is not a de Polignac number, because 1201778623 - 2¹³ = 1201770431 is a prime.

It is a super-2 number, since 2×1201778623² = 2888543717399552258, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1201778653) 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, 12411 + ... + 50572.

It is an arithmetic number, because the mean of its divisors is an integer number (300465172).

Almost surely, 2^1201778623 is an apocalyptic number.

1201778623 is a deficient number, since it is larger than the sum of its proper divisors (82065).

1201778623 is an equidigital number, since it uses as much as digits as its factorization.

1201778623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82064.

The product of its (nonzero) digits is 28224, while the sum is 37.

The square root of 1201778623 is about 34666.6788573697. The cubic root of 1201778623 is about 1063.1833291630.

The spelling of 1201778623 in words is "one billion, two hundred one million, seven hundred seventy-eight thousand, six hundred twenty-three".