77436021 has 16 divisors (see below), whose sum is σ = 113291136. Its totient is φ = 46752576.

The previous prime is 77436019. The next prime is 77436067. The reversal of 77436021 is 12063477.

It is not a de Polignac number, because 77436021 - 2¹ = 77436019 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 77436021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77436521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16665 + ... + 20798.

It is an arithmetic number, because the mean of its divisors is an integer number (7080696).

Almost surely, 2^77436021 is an apocalyptic number.

It is an amenable number.

77436021 is a deficient number, since it is larger than the sum of its proper divisors (35855115).

77436021 is a wasteful number, since it uses less digits than its factorization.

77436021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37532.

The product of its (nonzero) digits is 7056, while the sum is 30.

The square root of 77436021 is about 8799.7739175504. The cubic root of 77436021 is about 426.2335942522.

Adding to 77436021 its reverse (12063477), we get a palindrome (89499498).

The spelling of 77436021 in words is "seventy-seven million, four hundred thirty-six thousand, twenty-one".