61978501 has 8 divisors (see below), whose sum is σ = 67841144. Its totient is φ = 56272320.

The previous prime is 61978493. The next prime is 61978531. The reversal of 61978501 is 10587916.

It can be written as a sum of positive squares in 4 ways, for example, as 11937025 + 50041476 = 3455^2 + 7074^2 .

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

It is not a de Polignac number, because 61978501 - 2³ = 61978493 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61978531) 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, 38286 + ... + 39871.

It is an arithmetic number, because the mean of its divisors is an integer number (8480143).

Almost surely, 2^61978501 is an apocalyptic number.

61978501 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

It is an amenable number.

61978501 is a deficient number, since it is larger than the sum of its proper divisors (5862643).

61978501 is a wasteful number, since it uses less digits than its factorization.

61978501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78231.

The product of its (nonzero) digits is 15120, while the sum is 37.

The square root of 61978501 is about 7872.6425677786. The cubic root of 61978501 is about 395.7434079848.

The spelling of 61978501 in words is "sixty-one million, nine hundred seventy-eight thousand, five hundred one".