78406949 has 4 divisors (see below), whose sum is σ = 78644160. Its totient is φ = 78169740.

The previous prime is 78406927. The next prime is 78406961. The reversal of 78406949 is 94960487.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78406949 is a prime.

It is a super-2 number, since 2×78406949² = 12295299302977202, 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 (78406919) 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, 118109 + ... + 118770.

It is an arithmetic number, because the mean of its divisors is an integer number (19661040).

Almost surely, 2^78406949 is an apocalyptic number.

It is an amenable number.

78406949 is a deficient number, since it is larger than the sum of its proper divisors (237211).

78406949 is a wasteful number, since it uses less digits than its factorization.

78406949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237210.

The product of its (nonzero) digits is 435456, while the sum is 47.

The square root of 78406949 is about 8854.7698445527. The cubic root of 78406949 is about 428.0076369936.

The spelling of 78406949 in words is "seventy-eight million, four hundred six thousand, nine hundred forty-nine".