77953950781 has 8 divisors (see below), whose sum is σ = 89250180480. Its totient is φ = 66697708848.

The previous prime is 77953950757. The next prime is 77953950803. The reversal of 77953950781 is 18705935977.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 77953950781 - 2¹³ = 77953942589 is a prime.

It is a super-2 number, since 2×77953950781² (a number of 23 digits) 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 (77953959781) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9992761 + ... + 10000558.

It is an arithmetic number, because the mean of its divisors is an integer number (11156272560).

Almost surely, 2^77953950781 is an apocalyptic number.

It is an amenable number.

77953950781 is a deficient number, since it is larger than the sum of its proper divisors (11296229699).

77953950781 is a wasteful number, since it uses less digits than its factorization.

77953950781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19993883.

The product of its (nonzero) digits is 16669800, while the sum is 61.

The spelling of 77953950781 in words is "seventy-seven billion, nine hundred fifty-three million, nine hundred fifty thousand, seven hundred eighty-one".