647499891974 has 16 divisors (see below), whose sum is σ = 1048445850480. Its totient is φ = 298136250720.

The previous prime is 647499891887. The next prime is 647499891979. The reversal of 647499891974 is 479198994746.

It is a super-2 number, since 2×647499891974² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 647499891895 and 647499891904.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647499891979) 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, 29566064 + ... + 29587955.

It is an arithmetic number, because the mean of its divisors is an integer number (65527865655).

Almost surely, 2^647499891974 is an apocalyptic number.

647499891974 is a deficient number, since it is larger than the sum of its proper divisors (400945958506).

647499891974 is a wasteful number, since it uses less digits than its factorization.

647499891974 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59154455.

The product of its digits is 987614208, while the sum is 77.

The spelling of 647499891974 in words is "six hundred forty-seven billion, four hundred ninety-nine million, eight hundred ninety-one thousand, nine hundred seventy-four".