649421972 has 6 divisors (see below), whose sum is σ = 1136488458. Its totient is φ = 324710984.

The previous prime is 649421953. The next prime is 649421987. The reversal of 649421972 is 279124946.

It can be written as a sum of positive squares in only one way, i.e., 370331536 + 279090436 = 19244^2 + 16706^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81177743 + ... + 81177750.

It is an arithmetic number, because the mean of its divisors is an integer number (189414743).

Almost surely, 2^649421972 is an apocalyptic number.

It is an amenable number.

649421972 is a deficient number, since it is larger than the sum of its proper divisors (487066486).

649421972 is a wasteful number, since it uses less digits than its factorization.

649421972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162355497 (or 162355495 counting only the distinct ones).

The product of its digits is 217728, while the sum is 44.

The square root of 649421972 is about 25483.7589848907. The cubic root of 649421972 is about 865.9822545953.

The spelling of 649421972 in words is "six hundred forty-nine million, four hundred twenty-one thousand, nine hundred seventy-two".